МИНКИН Владимир Исаакович (h=36)sfedu.ru/international/wp-content/uploads/2012/12/LIST1.doc · Web viewh=36) V.I. Minkin, O.A. Osipov, Yu.A. Zhdanov. Dipole

Vladimir MINKIN (h=36)1. V.I. Minkin, O.A. Osipov, Yu.A. Zhdanov. Dipole Moments in Organic Chemistry. Plenum Press: New York. 1970. 2. V.I. Minkin, L.P. Olekhnovich, Yu.A. Zhdanov. Molecular Design of Tautomeric Compounds. Kluwer Publ. Dordrecht-Boston-Tokyo. 1988. 3. V.I. Minkin, B.Ya. Simkin, R.M. Minyaev. Quantum Chemistry of Organic Compounds. Mechanisms of Reactions. Springer Verlag. Berlin. 1990. 4. V.I. Minkin, M.N. Glukhovtsev, B.Ya. Simkin. Aromaticity and Antiaromaticity. Electronic and Structural Aspects. J.Wiley Intersci. New York. 1994. 5. R. Hoffmann, V.I. Minkin, B.K. Carpenter. Ockham's Razor and Chemistry. Bull. Soc. Chim. France, 1996,133, 117-130; Hyle (Intern. J. Philosophy), 1997, 3, 3-28.6. V. I. Minkin, R.M. Minyaev Cyclic Aromatic Compounds with Hypervalent Centers. Chem. Rev., 2001, 101, 1247-1265. (IF=40.197)7. A.V. Metelitsa, V.V. Lokshin, J.-C. Micheau, A. Samat, R. Guglielmetti, V.I. Minkin. "Photochromism and Solvatochromism of Push-Pull or Pull-Push Spiroindolinonaphthoxazines". Phys. Chem. Chem. Phys. 2002, 4, 4340-4345. (IF= 3.573)ABSTRACT: The photochromic and solvatochromic behaviour of 17 variously substituted spiroindoline naphthoxazines has been investigated in cyclohexane, toluene, acetonitrile and methanol in fluid solution. Specific parameters such as the wavelengths and the molar absorption coefficients of the closed spiro- and open merocyanine forms, together with the photocoloration and photobleaching quantum yields, rate constants and activation energies of thermal fading have been determined under continuous monochromatic irradiation. It has been shown that most of these parameters are closely related to the electron distribution on the highly conjugated photomerocyanines and on their quinoidal or zwitterionic character. Depending on the acceptor or donor properties and on the position of their substituents, three classes of compounds have been detected.8. R.M. Minyaev, V.I. Minkin, T.N. Gribanova, A.G. Starikov, R. Hoffmann. "Poly[n]prismanes. A Family of Stable Cage Structures with Half-Planar Carbon Centers". J. Org. Chem., 2003, 68 (22), 8588-8593. (IF= 4.450)ABSTRACT: A series of bi[n]prismanes and tri[n]prismanes (n = 3−6) containing n and 2n, respectively, tetracoordinated carbon centers with nonclassical bisphenoidal (half-planar) configuration has been designed computationally.9. V.I. Minkin. Photo-, Thermo-, Solvato- and Electrochromic Spiroheterocyclic Compounds. Chem. Rev., 2004, 104, 2751. (IF=40.197)10. A.D. Dubonosov, V.A. Bren, V.I. Minkin. The Photochemical Reactivity of the Norbornadiene- Quadricyclane System. In: Organic Photochemistry and Photobiology (Eds.W. Horspool, F. Lenci). Ch. 17, 1-34.CRC Press. Boca Raton-London-New York. 2004. 11. V.I. Minkin, R. M. Minyaev. Hypercoordinate Carbon in Polyhedral Organic Structures. Mendeleev Commun., 2004, 43-46. (IF=0.901)ABSTRACT: Carbon holds a unique position among the elements. It forms more than 14 millions of currently known organic compounds, structural organization of which is governed by the beautifully simple principles of tetravalence and tetrahedral stereochemical configuration. In the past decades, the edifice of the classical structural theory of organic compounds has been complemented with new approaches allowing a rational design of polyhedral clusters with hypercoordinate carbon centres.12. V.I. Minkin, A.V. Metelitsa, I.V. Dorogan, B.S. Lukianov, S.O. Besugliuy, J.-C. Micheau. "Spectroscopic and Theoretical Evidence for the Elusive Intermediate of the Photoinitiated and Thermal Rearrangements of Photochromic Spiropyrans". J. Phys. Chem. A, 2005, 109, 9605-9616. (IF=2.946)ABSTRACT: Spectral properties and photochromic behavior of a series of novel 1‘,3‘,3‘-trimethyl-1,2-tetramethylenespiro[7H-furo(3,2-f)-(2H-1)-benzopyran-7,2‘-indolines] 1−4 have been studied. The mechanism of the photoinitiated ring-opening reaction involves the formation of an acoplanar cis−cisoid intermediate, the lifetime of which in the case of 6-(tert-butyl) derivative 4 is long enough to observe its absorption and fluorescence spectra under conditions of continuous irradiation. The occurrence of the

intermediate on the reaction paths of the thermal and photochemical ring-opening processes has been also shown by the DFT and CIS calculations. The TD-B3LYP/6-31G**//HF/6-31G** calculated spectrum of the intermediate well matches that observed experimentally. For spiropyran 3 with a 6-NO2 group, kinetic and activation parameters of the photoinitiated coloration and dark bleaching reactions have been determined.13. R.M. Minyaev, T.N. Gribanova, V.I. Minkin, A.G. Starikov, R. Hoffmann. Planar and Pyramidal Tetracoordinate Carbon in Organoboron Compounds. J. Org. Chem. 2005, 70, 6693-6704. (IF= 4.450) ABSTRACT: Using previously proposed C(BH)2(CH)2 (16, 17) and C(CH)2B2 (22) systems with a central planar tetracoordinate carbon (ptC) atom linking two three-membered rings as building blocks, a series of stable structures containing two and three ptC centers within a molecule have been designed and computationally studied with the DFT (B3LYP/6-311+G**) method. Inclusion of a carbon atom ligated with π-accepting and σ-donating boron centers into at least one aromatic ring is critical for stabilization of a planar structure. A square pyramidal configuration at tetracoordinate carbon may be achieved in appropriately strained molecules such as [3.3.3.3]tetraborafenestrane 45 and others by surrounding the carbon with boron-centered ligands.14. I.D. Sadekov, G.A. Abakarov, V.I. Minkin. "Five-membered heterocycles with Vicinal Te and O Heteroatoms". Advances Heterocycl. Chem. 2006, 92, 55-82. (IF=1.818)15. V.I. Minkin. 'Photoswitchable Molecular Systems Based on Spiropyrans and Spirooxazines". In: Molecular Switches (B.L. Feringa and W.R. Browne eds.). Vol. 1. Ch.2. Pp. 37-80. Wiley-VCH. 2011.16. V.I. Minkin, A.V. Tsukanov, A.D. Dubonosov, V.A.Bren. "Tautomeric Schiff bases: Iono, solvate, thermo-and photochromism". J. Mol. Struct. 2011, 998, 179-191. (IF=1.634)ABSTRACT: The review article summarizes the recent data about novel tautomeric iono-, solvato-, thermo- and photochromic Schiff bases. This contribution focuses on the factors determining tautomeric equilibrium and on the investigations into the proton transfer mechanisms.17. T.N. Gribanova, R.M. Minyaev, V.I. Minkin. "Induced aromaticity and electron-count rules for bipyramidal and sandwich complexes of s- and d-metals". Open Org. Chem. J. 2011, 5 (Suppl. 1-M4), 62-78.ABSTRACT: Structures and stability of an extended series of bipyramidal, sandwich and sandwich-bipyramidal mixed complexes formed by conjugated cyclic hydrocarbons (CH)n with s- (Li, Na, K, Be, Mg, Ca) and d- (Cr, Mn, Fe) metals have been studied using DFT B3LYP/6-311+G(df,p) calculations. Stable structures of the compounds satisfy a general (6n + 6d + 12c) electron-count rule, where n stands for total number of the basal hydrocarbon rings, d is total number of d-metal centers (or separate sandwich moieties) and c is total number of apical metal-carbonyl groups. It is shown that stabilization of the studied polyhedral organometallic structures (induced aromaticity) is caused by filling 6π-electronic shells of basal (4-6)-membered cycles provided by donation of additional electrons from metal centers thereby acquiring closed 18-electron shells.18. A.A. Milov, R.M. Minyaev, V.I. Minkin. "Intramolecular Hypervalent Interaction in the Conjugate Five-Membered Rings". J. Phys. Chem. A, 2011, 115, 12973-12982 (IF=2.946)ABSTRACT: The intramolecular hypervalent interaction between the electron abundant atomic centers X and Y belonging to the IV–VI groups and second and fourth periods has been computationally studied on a model quasi-cyclic conjugate five-membered ring system 9 using the CCSD/6-311+G** and DFT B3LYP/6-311+G** methods. Electronic and structural factors affecting the strength and geometrical characteristics of the hypervalent X←Y interaction were analyzed based on the quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analyses. The donor–acceptor nY→σ*XR interaction has been shown to be the central factor correlating all important properties of the studied hypervalently bonded compounds 9.19. V.I. Minkin, A.A. Starikova, R.M. Minyaev Computational design of valence tautomeric adducts of CoII diketonates with redox-active o-benzoquinone1 ligands // Dalton Trans., (2012), DOI:10.1039/c2dt31567j. (IF=3.838)ABSTRACT: A new concept for the structural design of valence tautomeric (VT) metal complexes involving the formation of stable adducts of a tetracoordinate transition metal complex with a suitable bidentate redox-active ligand has been computationally studied using the DFT B3LYP*/6-311++G(d,p) method. The

calculations, performed on a series of adducts of CoII diketonates with o-benzoquinone and its mono- and diimines, showed that the mixed-ligand complexes of bis-(hexafluoroacetylacetonate) CoII with o-benzoquinone, o-benzoquinone imine and o-benzoquinone diimine satisfy the whole set of necessary conditions to be met by compounds exhibiting VT behaviour (stability of the adduct with respect to dissociation into the components, energy preference of the low-spin electronic state and thermally achievable energy barrier to intramolecular electron transfer determining the intrinsic mechanism of VT rearrangements). These compounds can be regarded as a feasible synthetic target of a broad series of mixed-ligand VT complexes. Aleksandr POZHARSKII (h=26)1. Pozharskii, A.F. Naphthalene 'proton sponges' Russian Chemical Reviews, 1998, 67 (1), pp. 1-24 (IF=2.644)ABSTRACT: Methods of synthesis, physicochemical and structural characteristics, and reactivity of 1,8-bis(dialkylamino)naphthalenes and some of their close analogues pertaining to the class of so-called 'proton sponges' are considered. The bibliography includes 154 references.2. Sorokin, V.I., Ozeryanskii, V.A., Pozharskii, A.F. A simple and effective procedure for the N-permethylation of amino-substituted naphthalenes, European Journal of Organic Chemistry, 2003, (3), pp. 496-498 (IF=3.329)ABSTRACT: A wide range of amino-substituted naphthalenes can be N-permethylated by the system Me2SO4/Na2CO3/H2O (alcohols) with good to excellent yields. Steric hindrance does not prevent the reaction. Some amines with electron-withdrawing groups, especially at nonconjugated positions, are also alkylated. The procedure allows the combination of a reduction (catalytic or by tin dichloride in acidic media) and a methylation in a one-pot process. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)3. Pozharskii, A.F. Naphthaldehydes, Russian Chemical Reviews, 2003, 72 (5), pp. 447-470 (IF=2.644)ABSTRACT: Data on methods for the preparation of naphthaldehydes, their physicochemical properties, structural characteristics and reactivities are generalised. Particular attention is given to procedures for formylation of naphthalenes and peri-interactions involving the aldehyde group in the α-position. The bibliography includes 201 references.4. Pozharskii, A.F., Ryabtsova, O.V., Ozeryanskii, V.A., Degtyarev, A.V., Kazheva, O.N., Alexandrov, G.G., Dyachenko, O.A. Organometallic Synthesis, Molecular Structure, and Coloration of 2,7-Disubstituted 1,8-Bis(dimethylamino)naphthalenes. How Significant Is the Influence of "Buttressing Effect" on Their Basicity?, Journal of Organic Chemistry, 2003, 68 (26), pp. 10109-10122 (IF=4.450)ABSTRACT: On treatment of 2,7-dilithio- (6a) and 2,7-bis(bromomagnesio)- (6b) naphthalenes with a number of electrophiles, new “proton sponge” derivatives 7a−e,g, containing iodo, methylthio, trimethylsilyl, methyl, n-butyl, and ethoxycarbonyl groups in ortho-positions to dimethylamino groups, have been synthesized. The investigation of their molecular structure, spectral characteristics, and basicity reveals that the latter is mainly determined by two groups of factors:  (1) the polar effect of ortho-substituents and (2) the so-called “buttressing effect” representing the complex combination of various sterical interactions of ortho-substituents with dimethylamino groups in corresponding bases and cations. A contradictory directionality of these interactions strongly reduces the importance of the buttressing effect in the case of compounds with bulky ortho-substituents, which is most clearly displayed in the absence of any relationship between the size of ortho-substituents and the basicity. On the contrary, for proton sponges having in ortho-positions the electron-donating groups with lesser steric demands, both the buttressing and the polar effects act in the same direction. This is the reason for the exceptionally high basicity of 2,7-dimethoxy- (2) and tetrakis(dimethylamino)- (3a) naphthalenes. It has been found that bis(trimethylsilyl)-bis(dimethylamino)naphthalene 7d has an in-out configuration of the NMe2 groups in the solid that is the first example of its kind in the series of naphthalene proton sponges. The origin of a yellow coloring of 2,7-disubstituted proton sponges is also discussed.5. Sorokin, V.I., Ozeryanskii, V.A., Pozharskii, A.F. Exclusive β-substitution in the reaction of octafluoronaphthalene with secondary amines, European Journal of Organic Chemistry, 2004, (4), pp. 766-769 (IF=3.329)

ABSTRACT: The reaction between octafluoronaphthalene and dimethylamine, pyrrolidine or piperidine in DMF, dimethyl (ethylene)urea (DMEU) or without solvent leads to the exclusive substitution of β-fluorine atoms giving naphthalene derivatives with four NR2 groups. This was proved by 19F NMR of the products and a crystal structure determination for 1,4,5,8-tetrafluoro-2,3,6,7-tetrakis(piperidin-1-yl)naphthalene. The main feature of the reaction in DMF was a transamidation process. The remaining four fluorine atoms in the synthesised tetraamines could be smoothly replaced by reduction with LiAlH4. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) 6. Szemik-Hojniak, A., Deperasińska, I., Buma, W.J., Balkowski, G., Pozharskii, A.F., Vistorobskii, N.V., Allonas, X. The asymmetric nature of charge transfer states of the cyano-substituted proton sponge, Chemical Physics Letters, 2005, 401 (1-3) , pp. 189-195 (IF=2.337)ABSTRACT: The geometric and electronic structure of 1,8-bis(dimethylamino)-4-cyano-naphthalene (DMAN-CN) and its mono-protonated cation (H+DMAN-CN) have been investigated by density functional theory (DFT) and time dependent density functional theory (TD-DFT) methods. Ground state geometry optimization leads to a significant structural asymmetry and polarity of both molecules. Vertical excitation energies and oscillator strengths calculated for the lower-lying excited singlet states of DMAN-CN are in excellent agreement with experimental absorption maxima in n-hexane. Similarly, it is found that experimentally observed solvatochromic shifts are favourably reproduced by the calculations. The calculations reveal that the S1 and S2 states of the neutral molecule and the S3 state of the cation are characterised by an asymmetric charge transfer, i.e., the two dimethylamino groups contribute unequally to the transfer of charge to the cyanonaphthalene moiety.7. Pozharskii, A.F., Gulevskaya, A.V. Pyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones: Marvelous substrates for study of nucleophilic substitution of hydrogen, Journal of Heterocyclic Chemistry, 2005, 42 (3) , pp. 375-385 (IF=1.220)ABSTRACT: The data on nucleophilic substitution reactions of hydrogen in 6,8-dimethylpyrimido[4,5-c]pyridazine- 5,7(6H,8H)-dione, its 3-chloride, N2-oxide and some other derivatives are reviewed. All these compounds possess a remarkable ability to undergo not only simple functionalizations but also tandem and cascade transformations leading to annelation of various heterocyclic rings.8. Pozharskii, A.F., Ryabtsova, O.V., Ozeryanskii, V.A., Degtyarev, A.V., Starikova, Z.A., Sobczyk, L., Filarowski, A. 2-α-hydroxybenzhydryl- and 2,7-di(α-hydroxybenzhydryl)-1,8- bis(dimethylamino)naphthalenes: The first examples of stabilization of in/out proton sponge conformers by intramolecular hydrogen bonding. The most flattened amino group ever participating in IHB, Tetrahedron Letters, 2005, 46 (23) , pp. 3973-3976 (IF=2.683) ABSTRACT: 2-(α-Hydroxybenzhydryl)- 6 and 2,7-di(α-hydroxybenzhydryl)-1,8-bis(dimethylamino)naphthalenes 8 have been shown to exist in crystals as in/out conformers stabilized by O–H⋯N intramolecular hydrogen bonding. In agreement with X-ray studies, the NMR data are also consistent with 7 retaining its in/out form in solution, whilst for 8 superimposed equilibrating in/out–out/in conformers are observed.9. Serduke, O.V., Gulevskaya, A.V., Pozharskii, A.F., Starikova, Z.A., Profatilova, I.A. Cycloalkano[1″,2″:4,5;4″,3″:4′,5′] bis(pyrrolo[2,3-c]pyrimido[5,4-e]pyridazines): Synthesis, structure and mechanism of their formation, Tetrahedron, 2006, 62 (4) , pp. 652-661 (IF=3.025)ABSTRACT: Reactions of 3-alkylamino-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones with cyclohexyl- and cycloheptylamines in the presence of AgPy2MnO4 produce novel cycloalkano[1″,2″:4,5;4″,3″:4′,5′]bis(pyrrolo[2,3-c]pyrimido[5,4-e]pyridazines). Detailed information concerning the scope and mechanism of these transformations is discussed.10. Pozharskii, A.F., Ryabtsova, O.V. Organolithium and organomagnesium compounds of the naphthalene series in organic synthesis, Russian Chemical Reviews, 2006, 75 (8) , pp. 709-736 (IF=2.644)ABSTRACT: The review summarises procedures for the synthesis of organolithium and organomagnesium compounds of the naphthalene series, including binaphthyls, the properties of these compounds and their use in organic synthesis.11. Gulevskaya, A.V., Pozharskii, A.F. Nucleophilic Aromatic Substitution of Hydrogen as a Tool for Heterocyclic Ring Annulation, Advances in Heterocyclic Chemistry, 2007, 93 , pp. 57-115 (IF=1.818)

ABSTRACT: SNH methodology finds significant use in organic synthesis. A major advantage of this methodology is that it eliminates the necessity of first introducing a good leaving group into an aromatic substrate. Moreover, in classical SNipso reactions an acid, such as HHal, H2SO4 or HNO2 is normally liberated that has to be scavenged. However, in SNH processes, a water molecule is typically formed that can contribute to “green chemistry.” This chapter deals with SNH cyclizations. SNH based heterocyclizations allow the synthesis of a great variety of heterocyclic structures differing in ring size, number of heteroatoms and their type, and degree of unsaturation. Various arenes and hetarenes with appropriate electron deficiency can be used as substrates. In context to future prospects, it is observed that a large number of known SNH cyclizations deals with the pyrrole ring closure, therefore search for new substrates, reagents, and cyclization schemes for the annulation of other heterocyclic rings is desirable. It is also important to optimize reaction conditions as many existing transformations do not provide high enough yields.12. Pozharskii, A.F., Degtyarev, A.V., Ryabtsova, O.V., Ozeryanskii, V.A., Kletskii, M.E., Starikova, Z.A., Sobczyk, L., Filarowski, A. 2-α-hydroxyalkyl- and 2,7-di(α-hydroxyalkyl)-1,8- bis(dimethylamino)naphthalenes: Stabilization of nonconventional in/out conformers of "proton sponges" via n⋯H-O intramolecular hydrogen bonding. A remarkable kind of tandem nitrogen inversion, Journal of Organic Chemistry, 2007, 72 (8) , pp. 3006-3019 (IF=4.450)ABSTRACT: A regular set of 2-(α-hydroxymethyl)- and 2,7-di(α-hydroxymethyl)-1,8-bis(dimethylamino)naphthalenes has been prepared. Their X-ray, NMR, and IR studies have demonstrated that in tertiary mono-alcohols the orientation of free nitrogen electron pairs in crystals and solution corresponds to nonconventional in/out conformers stabilized by O−H···N intramolecular hydrogen bonding. For tertiary 2,7-dialcohols, the superimposed equilibrating in/out−out/in nitrogen invertomers are observed in solution. Unlike this, primary and secondary mono- and dialcohols commonly exist in the in/in form, which is typical for the parent proton sponge and the majority of its derivatives.13. Serdyuk, O.V., Gulevskaya, A.V., Pozharskii, A.F., Avakyan, V.E. Benzobis(pyrrolopyrimidopiridazines): Molecular structure and properties of the first π-electronic analogues of dibenzo[a,o]picene, Journal of Heterocyclic Chemistry, 2008, 45 (1) , pp. 195-199 (IF=1.220)ABSTRACT: Molecular structure, aromaticity and some spectral properties of benzobis(pyrrolopyrimidopiridazines) 2 that are the first -electronic analogues of the still unknown dibenzo[a,o]picene are discussed.14. Gulevskaya, A.V., Burov, O.N., Pozharskii, A.F., Kletskii, M.E., Korbukova, I.N. Oxidative alkylamination of azinones as a direct route to aminoazinones: study of some condensed diazinones, Tetrahedron, 2008, 64 (4) , pp. 696-707 (IF=3.025)ABSTRACT: Oxidative alkylamination of azinones is a promising method for the preparation of a great variety of alkylaminoazinones. Treatment of 6,8-dimethyl-2-R-pyrimido[4,5-c]pyridazin-3,5,7(2H,6H,8H)-triones 7, 1,3-dimethyl-5-R-pteridin-2,4,6(1H,3H,6H)-triones 8 and 1,3,6-trimethylpyrimido[4,5-d]pyrimidin-2,4,7(1H,3H,6H)-trione 9 with alkylamine/AgPy2MnO4 or alkylamine/KMnO4 has been shown to produce their 4-, 7- and 5-alkylamino derivatives, respectively, in good yields. While 1-methylquinoxalin-2(1H)-one 10 is smoothly alkylaminated under the above conditions giving 3-alkylamino derivatives, quinoxaline itself does not take part in this reaction. Factors influencing oxidative alkylamination of azinones and a regioselectivity of the process are discussed.15. Degtyarev, A.V., Ryabtsova, O.V., Pozharskii, A.F., Ozeryanskii, V.A., Starikova, Z.A., Sobczyk, L., Filarowski, A. 2,7-Disubstituted proton sponges as borderline systems for investigating barrier-free intramolecular hydrogen bonds. Protonated 2,7-bis(trimethylsilyl)- and 2,7-di(hydroxymethyl)-1,8-bis(dimethylamino)naphthalenes, Tetrahedron, 2008, 64 (27) , pp. 6209-6214 (IF=3.025)ABSTRACT: Protonated 2,7-bis(trimethylsilyl)- and 2,7-di(hydroxymethyl)-1,8-bis(dimethylamino)naphthalenes have been prepared and studied by a combination of X-ray crystallography at room and low temperatures, IR and NMR spectroscopic techniques in conjunction with quantum-chemical calculations. It was demonstrated that the intramolecular [NHN]+ hydrogen bond in the 2,7-bis(trimethylsilyl) system, being sterically compressed, is the shortest among all known aromatic diamine systems. Nevertheless, as it is evidenced by the primary 1H/2H isotope effect, IR spectra and MP2 calculations, a double minimum potential for the proton motion still exists with a very low barrier estimated

to be about 0.7 kcal/mol. An influence of a counter-anion on the NH proton involving the spatially hindered H-bond is also considered.16. Pozharskii, A.F., Degtyarev, A.V., Ozeryanskii, V.A., Ryabtsova, O.V., Starikova, Z.A., Borodkin, G.S. 1,8,1′,8′-Tetrakis(dimethylamino)-2,2′- dinaphthylmethanols: Double in/out proton sponges with low-barrier hydrogen-bond switching, Journal of Organic Chemistry, 2010, 75 (14) , pp. 4706-4715 (IF=4.450)ABSTRACT: Previously unknown bis[1,8-bis(dimethylamino)naphth-2-yl]phenylmethanol (5) and bis[1,8-bis(dimethylamino)naphth-2-yl]methanol (6) have been obtained and studied by combination of X-ray, NMR, and IR techniques at variable temperature. It has been established that both proton sponge units in the solid tertiary alcohol 5 exist in nonconventional in/out form, one of which is fixed by intramolecular O−H···N hydrogen bonding. In solution, a fast interconversion of two isoenergetic hydrogen chelates occurs which can be frozen below 183 K. Unlike this, the secondary alcohol 6 in the solid at 100 K adopts the in/out−in/in conformation and at 293 K demonstrates a kind of dynamic behavior which can be described as temperature-driven dimer-induced rechelation. In solution under ambient conditions 6 exists as an equilibrating mixture of chelated and unchelated monomeric forms in a 1:1.8 molar ratio.17. Gulevskaya, A.V., Van Dang, S., Tyaglivy, A.S., Pozharskii, A.F., Kazheva, O.N., Chekhlov, A.N., Dyachenko, O.A. A novel tandem cyclization of condensed 2,3-dialkynylpyrazines into [1,2,3]triazolo[1′,5′;1,2]pyrido[3,4-b]pyrazines promoted by sodium azide, Tetrahedron, 2010, 66 (1) , pp. 146-151 (IF=3.025)ABSTRACT: 6,7-Dialkynyl-1,3-dimethylpteridine-2,4(1H,3H)-diones and 2,3-dialkynylquinoxalines have been shown to react with sodium azide in DMF at room temperature giving rise 9,11-dimethyl-[1,2,3]triazolo[1′,5′;1,2]pyrido[4,3-g]pteridine-8,10(9H,11H)-diones and [1,2,3]triazolo[1′,5′;1,2]pyrido[3,4-b]quinoxalines. A novel tandem cyclization involves 1,3-dipolar cycloaddition of an azide ion to the carbon–carbon triple bond followed by intramolecular nucleophilic addition of the intermediate 1,2,3-triazole N-anion to another CC bond.18. Pozharskii, A.F., Povalyakhina, M.A., Degtyarev, A.V., Ryabtsova, O.V., Ozeryanskii, V.A., Dyablo, O.V., Tkachuk, A.V., (...), Dyachenko, O.A. Naphthalene proton sponges as hydride donors: Diverse appearances of the tert-amino-effect, Organic and Biomolecular Chemistry, 2011, 9 (6) , pp. 1887-1900 (IF=3.696)ABSTRACT: It has been shown that the 1-NMe2 group in the 2-substituted 1,8-bis(dimethylamino)naphthalenes (proton sponges) can intramolecularly donate a hydride ion to an appropriate electron-accepting ortho-substituent such as diarylcarbenium ion, β,β′-dicyanovinyl or methyleneiminium group. This produces the 1-N+(Me)CH2 functionality and triggers a number of further transformations (tert-amino effect) including peri-cyclization, ortho-cyclization or hydrolytic demethylation. In each particular case, the course of the reaction is determined by the nature of the ortho-substituent and the most potent nucleophile presenting in the reaction mixture. For 2,7-disubstituted 1,8-bis(dimethylamino)naphthalenes, two types of tandem tert-amino effect with the involvement of both peri-NMe2 groups have been registered. The conclusion was made that proton sponges are generally more active in the tert-amino reactions than the corresponding monodimethylaminoarenes. This is ascribed both to higher electron donor ability of proton sponges and markedly shortened distance between electrophilic Cα-atom in the ortho-substituent and hydrogen atoms of the nearest NMe2 group. Most conversions observed proceed in good to high yields and are useful for the preparation of derivatives of benzo[h]quinoline, quino[7,8:7′,8′]quinoline, 2,3-dihydroperimidine, N,N,N′-trimethyl-1,8-diaminonaphthalene and proton sponge itself.19. Povalyakhina, M.A., Antonov, A.S., Dyablo, O.V., Ozeryanskii, V.A., Pozharskii, A.F. H-bond-assisted intramolecular nucleophilic displacement of the 1-NMe 2 group in 1,8-bis(dimethylamino)naphthalenes as a route to multinuclear heterocyclic compounds and strained naphthalene derivatives, Journal of Organic Chemistry, 2011, 76 (17) , pp. 7157-7166 (IF=4.450)ABSTRACT: It has been shown that azomethines, hydrazones, and oximes derived from 2(7)-carbonyl derivatives of 1,8-bis(dimethylamino)naphthalene can undergo acid-catalyzed heterocyclization leading to a nucleophilic displacement of the 1-NMe2 group. The process is believed to be directly connected with the proton sponge nature of the substrates, in which 1-NMe2, being a poor leaving group, is preliminary activated via the formation of a chelated protonated form. A number of difficult to access derivatives of

benzo[g]indazole, benzo[g]quinazoline, naphtho[2,1-d]isoxazole, and 8-dimethylamino-1-naphthol have been prepared in moderate to high yields.20. Gulevskaya, A.V., Pozharskii, A.F. Synthesis of pteridines fused to heterocycles, Russian Chemical Reviews, 2011, 80 (6) , pp. 495-529 (IF=2.644)ABSTRACT: The known methods for the synthesis of pteridines fused to other heterocycles, including natural compounds, are reviewed. The data are systematized according to the type of the fused ring.21. Gulevskaya, A.V., Nguyen, H.T.L., Tyaglivy, A.S., Pozharskii, A.F. New insight into anionic cyclizations of alkynyl- and ortho- dialkynylarenes: A specific reactivity of 3-alkynyl-2-chloro- and 2,3-dialkynylquinoxalines and related compounds toward CH-acids' carbanions, Tetrahedron, 2012, 68 (2) , pp. 488-498 (IF=3.025)ABSTRACT: The reactivity of 3-alkynyl-2-chloroquinoxalines, 2,3-dialkynylquinoxalines, and some related pyrazine derivatives toward carbanions of the CH-acids (malononitrile, ethyl cyanoacetate, diethyl malonate, 1,3-dimethylbarbituric acid) has been studied. Most of the observed reactions proceeded as tandem or cascade cyclizations yielding polynuclear heterocyclic compounds. The process starts with the addition of a nucleophile to an alkyne triple bond. Depending on the nature of the used C-nucleophile, the thus formed anionic adduct underwent further cyclization via (i) intramolecular nucleophilic substitution of the chlorine atom, (ii) intramolecular acylation of the ring nitrogen atom by the ester side chain or (iii) intramolecular nucleophilic attack on the second CC bond. Reactions of 3-alkynyl-2-chloro- and 2,3-dialkynylpyrazines with 1,3-dimethylbarbituric acid in the presence of t-BuOK were accompanied by recyclization of the 1,3-dimethylbarbituric acid moiety.22. Dyablo, O.V., Shmoilova, E.A., Pozharskii, A.F., Ozeryanskii, V.A., Burov, O.N., Starikova, Z.A. 4,5-bis(dimethylamino)quinolines: Proton sponge versus azine behavior, Organic Letters, 2012, 14 (16) , pp. 4134-4137 (IF=5.862)ABSTRACT: Two first representatives, 5 and 6, of the still unknown 4,5-bis(dimethylamino)quinoline have been synthesized and studied. While the former, being protonated either at the peri-NMe2 groups or at the ring nitrogen, has been shown to display properties of both a proton sponge and azine, its counterpart 6 behaves exclusively as azine giving only a quinolinium salt.23. Gulevskaya, A.V., Lazarevich, R.Y., Pozharskii, A.F. Electrophilic cyclizations of 2,3-dialkynylquinoxalines and 1,2-dialkynylbenzenes: a comparative study, Tetrahedron, 2012, Article in Press (IF=3.025)

Ruslan MINYAEV (h=22)1. V.I. Minkin and R.M. Minyaev, Aromatic stabilization of the organochalcogen compounds with intramolecular X¬O (X=S, Se, Te) coordination. Mendeleev Commun., 2000, №5, 171-173. (IF=0.901)ABSTRACT: The ab initio MP2/LanL2DZ calculations predict a significant contribution of cyclic π-electron delocalization to the stabilization of the trans–cis–cis conformation of derivatives of β-chalcogenovinylaldehydes 1 with the intramolecular Chalc←O coordination.2. R.M. Minyaev and V.I. Minkin Inramolecular hypervalent O→Cl interaction in the chloronium cations: an ab initio study Mendeleev Commun., 2000, №5, 173-174 (IF=0.901)ABSTRACT: The ab initio [MP2(fu)/6-31G**] and DFT (B3LYP/6-31+G**) calculations predict that the strong hypervalent O→Cl interaction stabilises the cyclic and bicyclic heteropentalene structures of chloronium cations. 3. R.M. Minyaev, V.I. Minkin, T.N. Gribanova, and A.G. Starikov Low-energy barrier B4 ring puckering rearrangement of 1,6-diaza-closo-hexaborane: ab initio study. Mendeleev Commun., 2001, N4, p.132-134. (IF=0.901)ABSTRACT: The ab initio [MP2(fu)/6-311+G**] and DFT (B3LYP/6-311+G**) calculations predict stable structures of closo-diazaboranes 1,6-N2B4H4 and 1,2-N2B4H4, with the low-energy barrier B4 ring puckering rearrangement occurring in the 1,6-N2B4H4 stable structure.4. V.I. Minkin and R.M. Minyaev, Cyclic Aromatic Systems with Hypervalent Centers. Chem. Rev., 2001, v. 101, N5, pp.1247-1265. (IF=40.197)

5. R.M. Minyaev, T.N. Gribanova, A.A. Milov, A.G. Starikov and V.I. Minkin. Novel aromatic borafluorole, fluoraborabenzene and diborafluorabenzenes novel aromatic heterocyclic systems: an ab initio study, Mendeleev Commun., 2002, N2, p.61-63. (IF=0.901)ABSTRACT: The ab initio [MP2(fu)/6-311+G**] and DFT (B3LYP/6-311+G**) calculations predict aromatic stabilization of the planar structures of borafluorole, fluoraborabenzene and diborafluorabenzenes, boron-containing heterocycles with hypercoordinated fluorine centres.6. V.I. Minkin, R.M. Minyaev, R. Hoffmann, "Non-classical structures of organic compounds: unusual stereochemistry and hypercoordination ", Russ. Chem. Rev., 2002, 71 (11), 869–892 (IF=2.644)ABSTRACT: Non-classical structures of organic compounds are defined as molecules containing non-tetrahedral tetracoordinate and/or hypercoordinate carbon atoms. The evolution of the views on this subject is considered and the accumulated theoretical and experimental data on the structures and dynamic transformations of non-classical organic compounds are systematised. It is shown that computational analysis using the methods and the software potential of modern quantum chemistry has now acquired high predictive capacity and is the most important source of data on the structures of non-classical compounds. The bibliography includes 227 references.7. R.M. Minyaev, V.I. Minkin, T.N. Gribanova and A.G. Starikov. Double p- and s-hydrogen bonding formic acid with pyrrole and imidazole: an ab initio and density function theory study, Mendeleev Commun., 2003, v.13, N5, p.207-209. (IF=0.901)ABSTRACT: Ab initio [MP2(fu)/6-311++G**] and DFT (B3LYP/6-311++G**) calculations predict that the cyclic 1:1 complexes of formic acid with pyrrole or imidazole are stabilised by non-conventional double hydrogen σ- and π-bonds.8. R.M. Minyaev, V.I. Minkin, T.N. Gribanova, and Andrei G Starikov. A hydrocarbon dication with a nonplanar hexacoordinated carbon Mendeleev Commun., 2004, N2, p.47-48. (IF=0.901)ABSTRACT: Ab initio [MP2(fu)/6-311G**] and DFT (B3LYP/6-311G**) calculations predict a stable hydrocarbon dication containing nonplanar hexacoordinated carbon.9. R.M. Minyaev, T.N. Gribanova, V.I. Minkin, A.G. Starikov, R. Hoffmann. Planar and Pyramidal Tetracoordinate Carbon in Organoboron Compounds. J. Org. Chem. 2005, 70, 6693-6704. (IF= 4.450) ABSTRACT: Using previously proposed C(BH)2(CH)2 (16, 17) and C(CH)2B2 (22) systems with a central planar tetracoordinate carbon (ptC) atom linking two three-membered rings as building blocks, a series of stable structures containing two and three ptC centers within a molecule have been designed and computationally studied with the DFT (B3LYP/6-311+G**) method. Inclusion of a carbon atom ligated with π-accepting and σ-donating boron centers into at least one aromatic ring is critical for stabilization of a planar structure. A square pyramidal configuration at tetracoordinate carbon may be achieved in appropriately strained molecules such as [3.3.3.3]tetraborafenestrane 45 and others by surrounding the carbon with boron-centered ligands.10. R.M. Minyaev, V.I. Minkin, T.N. Gribanova, and A.G. Starikov, Sandwich Compounds with Central Hypercoordinate Carbon, Nitrogen and Oxygen: a quantum-chemical study, Heteroatom Chemistry, 2006, vol.17, N6, p.1-11. (IF=1.243)ABSTRACT: Ab initio (mp2(fu)/6-311+g**) and dft (b3lyp/6-311+g**) calculations predict stable structures of sandwich compounds with the central carbon, nitrogen, and oxygen atoms surrounding lithium counterions between three-membered (BH)3 rings. The lithium counterions play a crucial role in the stabilization of these systems. The topological bader analysis performed for these sandwich systems demonstrates that the central atom is linked to the ligands by nine-bond paths and, consequently, should be regarded as a nine-coordinated atom. Such a coordination number of carbon is the highest for all known main group organoelement compounds. © 2006 wiley periodicals, inc. Heteroatom chem 17:464–474, 2006; published online in wiley interscience (www.interscience.wiley.com) Doi 10.1002/hc.2026811. O.A. Gapurenko, R.M. Minyaev and V.I. Minkin, Silicon analogue of pyramidane: a quantum-chemical study, Mendeleev Commun., 2011, 22, pp. 8-10. (IF=0.901)ABSTRACT: The DFT B3LYP/6-311+G(d,p) calculations predict that Si5R4 (R = SiH3, SiMe3) compounds may have stable effectively pyramidal structures with a bare apical silicon atom.12. Alexei A. Milov, Ruslan M. Minyaev, Vladimir I. Minkin, Intramolecular Hypervalent Interaction in the Conjugate Five-membered Rings. J. Phys. Chem. A., 2011,115 (45), pp 12973–12982. (IF=2.946)

ABSTRACT: The intramolecular hypervalent interaction between the electron abundant atomic centers X and Y belonging to the IV–VI groups and second and fourth periods has been computationally studied on a model quasi-cyclic conjugate five-membered ring system 9 using the CCSD/6-311+G** and DFT B3LYP/6-311+G** methods. Electronic and structural factors affecting the strength and geometrical characteristics of the hypervalent X←Y interaction were analyzed based on the quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analyses. The donor–acceptor nY→σ*XR interaction has been shown to be the central factor correlating all important properties of the studied hypervalently bonded compounds 9.13. T.N. Gribanova, R M. Minyaev, and V.I. Minkin, Multidecker tricarbonyl-bridged sandwich complexes of transition metals: structure, stability and electron-counting rules, Physical Chemistry Chemical Physics, 2012, 14, 14803-14809 (DOI:10.1039/C2CP41839H. (IF= 3.573)14. Ruslan M. Minyaev, Tatyana N. Gribanova, and Vladimir I. Minkin “Hyperbonding and Hypercoordination in the Main Group Chemistry”, Comprehensive Inorganic Chemistry II, 2013, vol.9, ch.4 (sent 2011, april).

Valerii OZERYANSKII (h=13)1. Ozeryanskii, V.A., Pozharskii, A.F., Milgizina, G.R., Howard, S.T. Synthesis and properties of 5,6-bis(dimethylamino)acenaphthylene: The first proton sponge with easily-modified basicity, Journal of Organic Chemistry, 2000, 65 (22) , pp. 7707-7709 (IF=4.450)2. Ozeryanskii, V.A., Pozharskii, A.F., Głowiak, T., Majerz, I., Sobczyk, L., Grech, E., Nowicka-Scheibe, J. X-ray diffraction and IR-spectroscopic studies on protonated 4-amino-1,8-bis(dimethylamino)naphthalene, Journal of Molecular Structure, 2002, 607 (1) , pp. 1-8 (IF=1.634)ABSTRACT: The crystal and molecular structure of monohydrated HBr adduct of 4-amino-1,8-bis(dimethylamino)naphthalene (DMAN·NH2) was determined at 100 K. The NHN+ bridges formed by protonation are asymmetrical although their length (2.56Å) would suggest to include them into shortest symmetric NHN hydrogen bonds. The asymmetry is caused by the NH2 groups interacting with H2O and Br− entities well reflected in the IR spectra. They are analysed by comparing with those of HClO4 salts. A characteristic band for short NHN bridges at about 500 cm−1 is observed with isotopic ratio (ISR) equal to 1.08 in contrast to effects usually found for protonated DMAN, where the ISR value exceeds √2. 3. Sorokin, V.I., Ozeryanskii, V.A., Pozharskii, A.F. A simple and effective procedure for the N-permethylation of amino-substituted naphthalenes, European Journal of Organic Chemistry, 2003, (3) , pp. 496-498 (IF=3.329)ABSTRACT: A wide range of amino-substituted naphthalenes can be N-permethylated by the system Me2SO4/Na2CO3/H2O(alcohols) with good to excellent yields. Steric hindrance does not prevent the reaction. Some amines with electron-withdrawing groups, especially at nonconjugated positions, are also alkylated. The procedure allows the combination of a reduction (catalytic or by tin dichloride in acidic media) and a methylation in a one-pot process. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)4. Bieńko, A.J., Latajka, Z., Sawka-Dobrowolska, W., Sobczyk, L., Ozeryanskii, V.A., Pozharskii, A.F., Grech, E., Nowicka-Scheibe, J. Low barrier hydrogen bond in protonated proton sponge. X-ray diffraction, infrared, and theoretical ab initio and density functional theory studies, Journal of Chemical Physics, 2003, 119 (8), pp. 4313-4319 (IF=3.333)ABSTRACT: A new proton sponge, 2,7-dibromo-1,8-bis(dimethylamino)naphthalene (Br2DMAN), and its protonated (HBr) or deuterated (DBr) forms were studied by using x-ray diffraction and infrared spectroscopy, as well as ab initio and density functional theory calculations. In the crystalline lattice of the Br2DMAN.HBr salt, symmetrical (NHN)+ hydrogen bonding of length 2.547(3) Å is observed. No deuterium geometrical isotope effect was detected. The structure refinement suggests disordering of protons between two equivalent positions at the nitrogen atoms. These findings are in agreement with infrared spectra, which are characterized by an intense band centered at ∼ 560 cm−1 assigned to the ν(NHN) protonic transition. Deuteration leads to a shift of this band to ∼ 340 cm−1, so that the isotopic ratio νH/νD (ISR) of 1.65 is characteristic of an unusual potential for the proton motion. The results of MP2 calculations are in fairly good agreement with the experimental data. The theoretical N…N hydrogen bond length is

2.575 Å, while the distance between the minima equals to ca. 0.5 Å with a barrier height of 0.70 kcal/mol. The calculated difference between the 0→1 proton (deuteron) levels is 509 (284) cm−1, giving an ISR value of 1.76.5. Sorokin, V.I., Ozeryanskii, V.A., Pozharskii, A.F., Starikova, Z.A. Hexa- and heptasubstitution in the interaction of octafluoronaphthalene with lithium dialkylamides: A new approach to the naphthalene 'proton sponges' Mendeleev Communications, 2004, 14 (1), pp. 14-16 (IF=0.901)ABSTRACT: The reaction of octafluoronaphthalene with lithium dimethylamide, pyrrolidide and piperidide was performed to synthesise polykis(dialkylamino)naphthalenes with up to seven dialkylamino groups as new strongly basic naphthalene ‘proton sponges’.6. Ozeryanskii, V.A., Pozharskii, A.F., Bieńko, A.J., Sawka-Dobrowolska, W., Sobczyk, L. [NHN]+ hydrogen bonding in protonated 1,8-bis(dimethylamino)-2, 7-dimethoxynaphthalene. X-ray diffraction, infrared, and theoretical ab initio and DFT studies, Journal of Physical Chemistry A, 2005, 109 (8) , pp. 1637-1642 (IF=2.946)ABSTRACT: Structural (X-ray diffraction), infrared spectroscopic, and theoretical MP2 and DFT studies on the HBr and DBr adducts of 1,8-bis(dimethylamino)2,7-dimethoxynaphthalene ((CH3O)2·DMAN) were performed. This particular proton sponge has been chosen for its strong basicity and display of the buttressing effect influencing the hydrogen bond dynamics and properties. The studies revealed a symmetric, planar DMAN·H+ cation with a short (NHN)+ hydrogen bond of 2.567(3) Å. The X-ray diffraction results suggest that the proton is in the central position in the bridge, while the calculations show two potential energy minima with the zero point energy level close to the top of the barrier. The infrared spectra display an (NHN)+ band at 488 cm-1 and an (NDN)+ band at 235 cm-1, respectively. It gives the isotopic ratio of 2.08, the highest value reported to date. Such a result suggests a peculiar shape of the potential for the proton motion, characterized by an extremely high positive anharmonicity. The calculations reproduce this particular potential, yielding an ISR value displaying a very good agreement with the experimental one. The anharmonic frequencies, however, show the discrepancy between the observed and calculated transitions.7. Ozeryanskii, V.A., Pozharskii, A.F., Koroleva, M.G., Shevchuk, D.A., Kazheva, O.N., Chekhlov, A.N., Shilov, G.V., Dyachenko, O.A. N,N,N′-Trialkyl-1,8-diaminonaphthalenes: Convenient method of preparation from protonated proton sponges and the first X-ray information, Tetrahedron, 2005, 61 (17), pp. 4221-4232 (IF=3.025)ABSTRACT: A simple procedure for the synthesis of N,N,N′-trialkyl-1,8-diaminonaphthalenes is described. It consists in partial demethylation (dealkylation) of commercially available proton sponge [1,8-bis(dimethylamino)naphthalene] and some of its derivatives at heating with HBr–KI–DMF system. Limitation, scope and a possible mechanistic pathway for the reaction are discussed. For isomeric 8-dimethylamino-1-methylamino- and 1-dimethylamino-8-methylamino-4-nitronaphthalenes, X-ray measurements have been conducted. The first examples of complete realkylation reactions in the naphthalene proton sponges are reported.8. Sorokin, V.I., Ozeryanskii, V.A., Borodkin, G.S. A new route to polykis(dialkylamino)benzenes and -naphthalenes based on protodefluorination of electron-rich fluoroaromatics: Anion radicals of arenes as a simple and effective alternative to 'classical' LAH-based systems, Synthesis, 2006, (1) , art. no. Z11505SS , pp. 97-102 (IF=2.466)ABSTRACT: A simple and effective procedure for protodefluorination of electron-rich fluoroaromatic compounds has been developed. It operates with aromatic anion radicals as reducing agents and shows superior results over ‘classical' lithium aluminum hydride based systems.9. Ozeryanskii, V.A., Pozharskii, A.F., Schilf, W., Kamieński, B., Sawka-Dobrowolska, W., Sobczyk, L., Grech, E. Novel polyfunctional tautomeric systems containing salicylideneamino and proton sponge moieties, European Journal of Organic Chemistry, 2006, (3) , pp. 782-790 (IF= 3.329)ABSTRACT: The first salicylidenearylamines containing a proton sponge residue with 5′-bromo (6), 5′-nitro (7), and 3′,5′-dinitro (8) substituents have been synthesized. X-ray diffraction and 1H, 13C, and 15N NMR and infrared spectra revealed that 6 and 7 contain very strong OHN bridges typical of o-hydroxy Schiff bases. Additional π-electron coupling with the dimethylaminonaphthyl ring is manifested both in geometrical and infrared parameters. In the case of 7, proton transfer to the imine nitrogen atom occurs in

the solid state, accompanied by a remarkable shortening of the OHN bridge (2.553 Å). In dinitro derivative 8, the OH proton jumps to the dimethylamino groups, giving a new tautomeric form with the formation of a homoconjugated [NHN]+ cation. Protonation of 6 and 7, affecting the (dimethylamino)naphthyl moiety, disrupts the π-coupling and makes these molecules, unlike common aromatic Schiff bases, highly sensitive to hydrolysis, while 8, being already self-protonated, equilibrates in wet DMSO with the corresponding salicylaldehyde and arylamine in a ca. 1:1 ratio at room temperature.10. Ozeryanskii, V.A., Milov, A.A., Minkin, V.I., Pozharskii, A.F. 1,8-Bis(dimethylamino)naphthalene-2,7-diolate: A simple arylamine nitrogen base with hydride-ion-comparable proton affinity, Angewandte Chemie - International Edition, 2006, 45 (9) , pp. 1453-1456 (IF= 13.455)ABSTRACT: The strongest nitrogen base is 1,8-bis(dimethylamino)naphthalene-2,7-diolate according to experimental data and DFT calculations. Its proton affinity (PA) is comparable to those of simple ions such as OH−, NH2−, and H−. The diaminonaphthalene diolate 2 is protonated at the neutral amino groups with extremely high gas-phase and solution proton affinity to form highly stable H-bonded conjugate acid 1. DMSO=dimethyl sulfoxide.11. Mekh, M.A., Ozeryanskii, V.A., Pozharskii, A.F. 5,6-Bis(dimethylamino)acenaphthylene as an activated alkene and 'proton sponge' in halogenation reactions, Tetrahedron, 2006, 62 (52) , pp. 12288-12296 (IF=3.025)ABSTRACT: It has been shown that 5,6-bis(dimethylamino)acenaphthylene in its reactions with X2 (X=Cl, Br, I) and N-X-succinimides behaves simultaneously as an electron-rich alkene or arene and proton sponge. Thus, addition of bromine or iodine to the C(1)C(2) bond is followed by immediate dehydrohalogenation leading to the formation of the corresponding 1(2)-(di)halogenoacenaphthylenes in good yields. Reaction with chlorine enables isolation of only 1,4,7-trichloro-5,6-bis(dimethylamino)acenaphthylene. With N-halosuccinimides, the halogenation is directed mainly by the steric bulk of the entering halogen and then by solvent polarity thus allowing the regioselective preparation of 1(2)- or 4(7)-(di)halides. Introduction of the third and fourth bromine atoms, but not chlorine, is accomplished by mono-N-demethylation. The pKa values of some new derivatives of acenaphthene and acenaphthylene proton sponges were measured by competitive transprotonation 1H NMR spectroscopy technique in DMSO. The X-ray molecular structures of 4,7-dichloro-5,6-bis(dimethylamino)acenaphthylene and its monoprotonated form are reported.12. Chmielewski, P., Ozeryanskii, V.A., Sobczyk, L., Pozharskii, A.F. Primary 1H/2H isotope effect in the NMR chemical shift of HCIO4 salts of 1,8-bis(dimethylamino)naphthalene derivatives, Journal of Physical Organic Chemistry, 2007, 20 (9) , pp. 643-648 (IF= 1.963)ABSTRACT: The primary 1H/2H isotope effect for a number of protonated naphthalene proton sponges (DMAN-s) was measured and correlated with the δ(1H) value and IR spectroscopic characteristics of the [NHN]+ hydrogen bonds. A particular role of the unusual anharmonicity expressed in the isotopic ratio ISR ≫ √2 is discussed when the fundamental vibrational levels are close to the barrier top for proton/deuteron motion. 14. Ozeryanskii, V.A., Shevchuk, D.A., Pozharskii, A.F., Kazheva, O.N., Chekhlov, A.N., Dyachenko, O.A. Protonation of naphthalene proton sponges containing higher N-alkyl groups. Structural consequences on proton accepting properties and intramolecular hydrogen bonding, Journal of Molecular Structure, 2008, 892 (1-3) , pp. 63-67 (IF=1.634)ABSTRACT: 1,8-Bis(dipropylamino)naphthalene and 1,8-di(pyrrolydin-1-yl)naphthalene as well as monoprotonated forms of the latter and of 1,8-di(piperidin-1-yl)naphthalene were structurally analyzed and compared with known data for 1,8-bis(dimethylamino)naphthalene and its protonated form. The N-alkyl groups enlarging the N…N distance (up to ∼2.9 Å) and changing the degree of conjugation between the NAlk2 and naphthalene moieties modify in a complex way the basicity (pKa values of conjugated acids) as well as the properties of intramolecular hydrogen bonds both in the solid state and in solution for a set of 1,8-bis(dialkylamino)naphthalenes.15. Ozeryanskii, V.A., Pozharskii, A.F., Artaryan, A.K., Vistorobskii, N.V., Starikova, Z.A. 1,8-Bis(dialkylamino)-4,5-dinitronaphthalenes and 4,5-bis(dimethylamino)- naphthalene-1,8-dicarbaldehyde as "push-pull" proton sponges: When and why formyl groups become stronger π-electron acceptors than nitro groups, European Journal of Organic Chemistry, 2009, (8) , pp. 1241-1248 (IF= 3.329)

ABSTRACT: Single-crystal X-ray studies of four representatives of “push–pull” proton sponges, namely 1,8-bis(dimethylamino)-, 1,8-bis(diethylamino)-, 1,8-bis(dipropylamino)-4,5-dinitronaphthalenes and 4,5-bis(dimethylamino)naphthalene-1,8-dicarbaldehyde have been performed at low and ambient temperatures. The most interesting and unexpected result is that the formyl groups in the peri-dialdehyde display stronger π-acceptor effects than the nitro groups. This phenomenon is ascribed to smaller steric demands of the CHO groups, their lower electrostatic repulsion, and specific packing forces. The naphthalene cores of all but one of the molecules are markedly twisted (21–26°) while that of the diethylamino derivative is not (<5°), providing different and somewhat unpredictable ways of resonance stabilization and steric relaxation. The through-conjugation in the above compounds is also discussed for gas and solution phases on the basis of theoretical calculations, UV/Vis and 1H NMR spectra.16. Boiko, L.Z., Sorokin, V.I., Filatova, E.A., Starikova, Z.A., Ozeryanskii, V.A., Pozharskii, A.F. Three examples of naphthalene proton sponges with extreme or unusual structural parameters. General view on factors influencing proton sponge geometry, Journal of Molecular Structure, 2011, 1005 (1-3) , pp. 12-16 (IF=1.634)ABSTRACT: X-ray measurements of four naphthalene proton sponges have been performed. They include 2,7-di(4-tolylethynyl)-1,8-bis(dimethylamino)naphthalene 4 together with its cation, 2,4-bis(trifluoroacetyl)-1,8-bis(dimethylamino)naphthalenes 16 and 2,6-difluoro-1,3,4,5,7,8-hexakis(dimethylamino)naphthalene 15. It has been disclosed that among all known proton sponge derivatives, compound 16 possesses the largest N⋯N distance and the strongest deviation of the NMe2 groups from the average ring plane while for compound 15 the related parameters are record small. A peculiarity of 2,7-diacetylene 4 is its unusually enhanced basicity contrasting with electron acceptor nature of 4-tolylethynyl group. An origin of the latter phenomena is discussed.17. Pozharskii, A.F., Ozeryanskii, V.A. Proton sponges and hydrogen transfer phenomena, Mendeleev Communications, 2012, 22 (3) , pp. 117-124 (IF=0.901)ABSTRACT: Recent advances in the studies of hydrogen transfer (protonation, hydrogen bonding, hydride transfer and CH acidity) in proton sponges, its influence on the structure, stereodynamics and reactivity of these superbasic compounds and the use of the above phenomena for modelling enzyme catalysis have been discussed.

Anatoliy METELITSA (h=12)1. Metelitsa, A.V., Micheau, J.C., Voloshin, N.A., Voloshina, E.N., Minkin, V.I. Kinetic and thermodynamic investigations of the photochromism and solvatochromism of semipermanent merocyanines, Journal of Physical Chemistry A, 2001, 105 (37), pp. 8417-8422 (IF= 2.946)ABSTRACT: The photochromic and solvatochromic behavior of four phenanthroline-containing spirooxazines bearing various alkyl long-chain substituents has been investigated in different polar and nonpolar solvents at various temperatures. These derivatives always appeared in an equilibrium mixture of spiro forms and open merocyanines. Depending on the substituents and the solvents, the percentage of the spontaneous merocyanine open form ranged from less than 10% to more than 30%. These results have been corroborated by independent NMR and photokinetic analysis. The main spectroscopic, thermodynamic, and photochromic parameters of such photo- and solvatochromic systems have been determined. Special illustrative diagrams showing quantitative substituent and solvent effects on absorption wavelengths, molar absorption coefficients, thermal equilibrium, interconversion rate constant, and quantum yields have been established. The two O-alkyl long-chain-substituted compounds 3 and 4 behave similarly, as do the N-alkyl derivatives 1 and 2. Opposition between polar and nonpolar solvents was also clearly illustrated. A global energy diagram including a short-lived cisoid merocyanine intermediate allows the interpretation of all solvent and temperature effects in terms of the relative solvation of the various short- and long-lived species and transition states. 2. Lokshin, V., Samat, A., Metelitsa, A.V. Spirooxazines: Synthesis, structure, spectral and photochromic properties, Russian Chemical Reviews, 2002, 71 (11), pp. 893-916 (IF=2.644) ABSTRACT: The review surveys synthetic approaches to spiro[1,4]oxazines belonging to one of the most promising classes of organic photochromes. The relationships between the structures of spirooxazines and

their spectral properties as well as characteristics of thermal and photoinduced processes are considered. The bibliography includes 201 references.3. Lokshin, V., Valès, M., Samat, A., Pèpe, G., Metelitsa, A., Khodorkovsky, V. A novel photoreversible photochromic system involving a hydrogen transfer/cyclization sequence, Chemical Communications, 2003, 9 (16), pp. 2080-2081 (IF=6.169)ABSTRACT: A novel photoreversible photochromic system, 3-(2-benzylbenzoyl)-1,2-R,R1-4(1H)-quinolinones/12-hydroxy-5-R-5a-R1-6-phenyl-5a,6-dihydrobenzo[b]acridin-11(5H)-ones, is described.4. Berthet, J., Micheau, J.-C., Metelitsa, A., Vermeersch, G., Delbaere, S. Multistep thermal relaxation of photoisomers in polyphotochromic molecules, Journal of Physical Chemistry A, 2004, 108 (50), pp. 10934-10940 (IF=2.946)ABSTRACT: UV irradiation of a polyphotochromic molecule bearing a spironaphthoxazine unit linked to a naphthopyran by a Z-ethenic bridge produces several interconverting nonequilibrium dihydrophenanthrenic photocyclized isomers. A quantitative kinetic analysis of the thermal evolution after photocyclization has been performed using 1H and 19F NMR spectroscopy at different temperatures. Spirooxazine (Spo) ring opening and TTC/CTC (i.e., trans−transoid−cis/cis−transoid−cis) isomerization occur reversibly, but only when the naphthopyran ring is closed. In contrast, naphthopyran ring opening is irreversible and is observed when the spirooxazine ring is either closed or open in the TTC configuration, but not from the CTC configuration. Activation parameters of the main isomerization processes have been determined. Relative stability of the various isomers (TTC > CTC > Spo) has been established. The use of model compounds bearing either a spirooxazine or a naphthopyran in a similar dihydrophenanthrenic environment confirms these specific reactivities and relative stabilities in accordance with PM-3 calculations.5. Metelitsa, A.V., Micheau, J.C., Besugliy, S.O., Gaeva, E.B., Voloshin, N.A., Voloshina, E.N., Samat, A., Minkin, V.I. Photochromic properties of six 5-O-n-alkyl, 6′-CN substituted spironaphthoxazines, International Journal of Photoenergy, 2004, 6 (4) , pp. 199-204 (IF=1.769)ABSTRACT: The photochromic properties of a series of six 5-O-n-alkyl, 6_-CN substituted spironaphthoxazines has been investigated in toluene and methanol solution. The 6_-CN and 5-O-n-alkyl substitutions lead to a bathochromic shift of the UV spectra of the closed forms. The λmax of the visible spectra of the open forms decrease with solvent polarity. Most of the photochromic parameters have been quantitatively determined. Among them, photocoloration and photobleaching quantum yields and molar absorption coefficients of the open forms have been derived from a numerical fitting of the photokinetic curves recorded under continuous monochromatic irradiation. Results show that the photo-steady-state properties are relatively independent of the 5-O-n-alkyl chain length, but are more sensitive to the size of the indolinic nitrogen substituent.6. Gaeva, E.B., Pimienta, V., Metelitsa, A.V., Voloshin, N.A., Minkin, V.I., Micheau, J.C. Solvation effects on spirooxazine to merocyanine thermal reversion kinetics in acetonitrile-water binary mixtures, Journal of Physical Organic Chemistry, 2005, 18 (4), pp. 315-320 (IF= 1.963)ABSTRACT: In solution, the photochromic molecule 5-methoxyspiro[indole-phenanthrolinoxazine] (SPO) is in equilibrium with its corresponding merocyanine open isomer. In pure acetonitrile, there is about 22.5% of the open form, whereas in acetonitrile–water binary solvents this proportion increases to more than 60% when the water molar fraction χ(H2O) is around 0.80. Irradiation in the visible range leads to a photobleached steady state in which the proportion of the merocyanine open isomer decreases significantly. When irradiation is switched off, a slow thermal reversion of the closed spirooxazine to the open merocyanine takes place until the initial equilibrium position is reached. Kinetic analysis of a whole set of relaxation curves recorded at various water contents was used to establish a model involving multiple equilibria between three merocyanines in different solvation states (solvated by acetonitrile, solvated by an acetonitrile–water complex and hydrated). Their relative proportions, which are dependent on the binary mixture composition, were determined, in addition to their corresponding visible spectra. 7. Minkin, V.I., Metelitsa, A.V., Dorogan, I.V., Lukyanov, B.S., Besugliy, S.O., Micheau, J.-C. Spectroscopic and theoretical evidence for the elusive intermediate of the photoinitiated and thermal rearrangements of photochromic spiropyrans, Journal of Physical Chemistry A, 2005, 109 (42) , pp. 9605-9616 (IF= 2.946)

ABSTRACT: Spectral properties and photochromic behavior of a series of novel 1‘,3‘,3‘-trimethyl-1,2-tetramethylenespiro[7H-furo(3,2-f)-(2H-1)-benzopyran-7,2‘-indolines] 1−4 have been studied. The mechanism of the photoinitiated ring-opening reaction involves the formation of an acoplanar cis−cisoid intermediate, the lifetime of which in the case of 6-(tert-butyl) derivative 4 is long enough to observe its absorption and fluorescence spectra under conditions of continuous irradiation. The occurrence of the intermediate on the reaction paths of the thermal and photochemical ring-opening processes has been also shown by the DFT and CIS calculations. The TD-B3LYP/6-31G**//HF/6-31G** calculated spectrum of the intermediate well matches that observed experimentally. For spiropyran 3 with a 6-NO2 group, kinetic and activation parameters of the photoinitiated coloration and dark bleaching reactions have been determined.8. Chernyshev, A.V., Voloshin, N.A., Raskita, I.M., Metelitsa, A.V., Minkin, V.I. Photo- and ionochromism of 5'-(4,5-diphenyl-1,3-oxazol-2-yl) substituted spiro[indoline-naphthopyrans], Journal of Photochemistry and Photobiology A: Chemistry, 2006, 184 (3) , pp. 289-297 (IF= 2.421)ABSTRACT: Photo- and ionochromism of two spiro[indoline-naphthopyran] derivatives with a 4,5-diphenyl-1,3-oxazol-2-yl substituent at the 5’-position has been investigated. The cyclic forms exhibit fluorescence and phosphorescence. In the presence of metal ions such as Zn(II), Cu(II), Mn(II), Co(II), Ni(II), Cd(II) the merocyanine isomers of the 5’-(4,5-diphenyl-1,3-oxazol-2-yl) substituted spironaphthopyrans forms metal complexes whose composition and stability strongly depends on the nature of a metal ion. Zn(II), Cd(II) and Mn(II) ions form 1:1 complexes, whereas with Co(II), Ni(II) and Cu(II) ions the formations of 1:2 complexes was also observed. For the first time stepwise stability constants and spectral properties of the prepared mono- and bis-complexes have been determined. The complexes formed by Cd(II) and Zn(II) ions exhibit fluorescence in 580–700 nm spectral region. Complexes with Mn(II) at 77 K display unusual narrow band fluorescence with a maximum at 730–760 nm. At room temperature solutions of the complexes with Cd(II), Zn(II), Mn(II) demonstrate negative photochromic behavior which make them promising building blocks for the construction of photodynamic chemosensors for metal ions.9. Shirinian, V.Z., Besugliy, S.O., Metelitsa, A.V., Krayushkin, M.M., Nikalin, D.M., Minkin, V.I. Novel photochromic spirocyclic compounds of thienopyrroline series: 1. Spiropyrans, Journal of Photochemistry and Photobiology A: Chemistry, 2007, 189 (2-3) , pp. 161-166 (IF= 2.421)ABSTRACT: Novel spiropyrans of the thienopyrroline series have been synthesized and their photochromic properties studied and compared with those of the indoline analogues. As compared with the indoline analogues, the absorption bands of the cyclic forms of the thienopyrroline spiropyrans are shifted to the blue spectral region, whereas those of the ring-opened forms are shifted to the red region. The merocyanine isomers of the thienopyrroline spiropyrans demonstrate greater thermal stability than their indoline analogues. At the same time thienopyrroline spiropyrans are more photodegradable and less fatigue resistant than the indoline congeners.10. Gaeva, E.B., Pimienta, V., Delbaere, S., Metelitsa, A.V., Voloshin, N.A., Minkin, V.I., Vermeersch, G., Micheau, J.C. Spectral and kinetic properties of a red-blue pH-sensitive photochromic spirooxazine, Journal of Photochemistry and Photobiology A: Chemistry, 2007, 191 (2-3) , pp. 114-121 (IF= 2.421)ABSTRACT: By means of UV/Vis absorption spectroscopy, NMR measurements and kinetic modelling, two spironaphthoxazine compounds bearing 5-OAlk substituent have been investigated in neutral and acidified ethanol media. The kinetics of ring opening/ring closure and the equilibrium constant, the quantum yield of photocoloration, the molar absorption coefficients of the neutral and protonated open forms and pKa values have been determined. A three-species photoreversible transformation between the closed form, the open form and the protonated open form has been observed in slightly acidified solutions.11. Krayushkin, M.M., Shirinian, V.Z., Shimkin, A.A., Mailian, A.K., Metelitsa, A.V., Bezugliy, S.O. Novel photochromic spiro compounds based on thieno[3,2-b]pyrroles, Journal of Physical Organic Chemistry, 2007, 20 (11), pp. 845-850 (IF= 1.963)ABSTRACT: Previously unknown spiro compounds of thienopyrroline series were synthesized by a convenient method starting from easily accessible 3-hydroxythiophene derivatives. The photochromic properties of spiro compounds of thienopyrroline series were studied.

12. Chernyshev, A.V., Metelitsa, A.V., Gaeva, E.B., Voloshin, N.A., Borodkin, G.S., Minkin, V.I. Photo- and thermochromic cation sensitive spiro[indoline-pyridobenzopyrans], Journal of Physical Organic Chemistry, 2007, 20 (11) , pp. 908-916 (IF= 1.963)ABSTRACT: The photo- and thermochromic behaviour of a series of spiro[indolinepyridobenzopyrans] 1–5 has been studied. The thermodynamic and kinetic parameters of the thermal equilibria between the ring-closed and ring-opened (merocyanine) isomeric forms of spiropyrans have been determined using UV–Vis absorption and 1H NMR spectroscopies techniques. The most stable form of 1-(2-hydroxyethyl)-spiro[indoline-pyridobenzopyran] 4 is represented by its trans-(hydroxystyryl)oxazolidineindoline isomer coexisting in acetone solution with the ring-closed spiroform. In the presence in solution of metal salts, spiro[indoline-pyridobenzopyrans] exhibit strong ionochromic effect due to the formation of complexes with the merocyanine ligand. The composition of the complexes formed by Zn2+ and Ni2+ ions has been determined with the use of spectrophotometric and electrospray ionisation mass spectroscopy techniques. The stepwise stability constants and spectral properties of the most stable 1:1 and 1:2 metal/merocyanine complexes have been determined. Selectivity of the complexation reaction depends on the position of the thermochromic equilibrium. 13. Besugliy, S.O., Metelitsa, A.V., Shirinian, V.Z., Krayushkin, M.M., Nikalin, D.M., Minkin, V.I. Novel photochromic spirocyclic compounds of thienopyrroline series: 2. Spirooxazines, Journal of Photochemistry and Photobiology A: Chemistry, 2009, 206 (2-3), pp. 116-123 (IF= 2.421)ABSTRACT: Photochromic properties of novel spirooxazines of the thienopyrroline series have been studied in comparison with those of an indoline analogue. Solvatochromism of the merocyanine photoisomers has been investigated using the Kamlet–Taft model. It has been found that inversion of the trends in the solvatochromic behavior of the spirooxazines takes place when passing from non-protogenic to protic solvents. Thienopyrroline spirooxazines possess relatively poor fatigue resistance. The origin of the processes causing their photodegradation has been studied.14. Nikolaeva, O.G., Tsukanov, A.V., Shepelenko, E.N., Lukyanov, B.S., Metelitsa, A.V., Kostyrina, O.Y., Dubonosov, A.D., Vladimir A. Bren, Minkin, V.I. Synthesis of novel iono- and photochromic spiropyrans derived from 6,7-dihydroxy-8-formyl-4-methyl-2H-chromene-2-one, International Journal of Photoenergy, 2009 , art. no. 238615 (IF=1.769)ABSTRACT: Novel photochromic spiropyrans (SPPs) containing -hydroxy group were synthesized and their spectral properties as well as abilities for complexation with metal ions studied. In solutions they exist as equilibrium mixture of spirocyclic (A) and merocyanine (B) isomers. The largest content of merocyanine form was found for the derivative with an electron-donating methyl group in position 5 of hetaryl fragment. The irradiation of SPPs in acetonitrile shifts the equilibrium to the B form. Similar effect causes the addition of metal cations due to formation of colored complexes with merocyanine isomers.15. Zakharova, M.I., Coudret, C., Pimienta, V., Micheau, J.C., Delbaere, S., Vermeersch, G., Metelitsa, A.V., Voloshin N.A., Minkin, V.I. Quantitative investigations of cation complexation of photochromic 8-benzothiazole-substituted benzopyran: Towards metal-ion sensors, Photochemical and Photobiological Sciences, 2010, 9 (2) , pp. 199-207 (IF= 2.584)ABSTRACT: The photochromic, thermochromic and metallochromic behaviour of a series of three spiro[indoline-8-(benzothiazol-2-yl)-benzopyrans] has been investigated. The thermodynamic and kinetic parameters of their thermal equilibrium between the ring-closed (spiro) and ring-opened (merocyanine) isomeric forms have been determined using UV-Vis absorption and 1H NMR spectroscopies. By adding Co(II) and Ni(II) ions in acetonitrile solution, 1:1 and 1:2 metal:merocyanine complexes are formed simultaneously. Using appropriate numerical methods, the kinetic analysis of the complexation allowed us to determine accurately key thermodynamic and spectroscopic parameters of the metal complexes. Results showed that the complexation strength is very sensitive to the size of the indoline nitrogen substituent. Complexation can be reversed by shining white light on the coloured complexes which regenerates the inactive spiropyran form, and releases the metallic ion; hence, these systems display fully reversible negative photochromism. The Zn(II) complexes exhibit intense fluorescence in the 600–800 nm wavelength range. All these behaviours make these spiropyrans bearing benzothiazole heterocycles promising building blocks for the future construction of photodynamic chemosensors for transition metal ions.

16. M.I. Zakharova , C. Coudret, V. Pimienta, J.C. Micheau, M. Sliwa, O. Poizat, G. Buntinx, S. Delbaere, G. Vermeersch, A.V. Metelitsa, N. Voloshin, V.I. Minkin, Kinetic modelling of the photochromism and metal complexation of a spiropyran dye: Application to the Co(II) - Spiroindoline- diphenyloxazolebenzopyran system, Dyes and Pigments, 2011, 89 (3) , pp. 324-329 (IF=3.126)ABSTRACT: A spirobenzopyran containing 6-chloro and 8-diphenyloxazole substituents has been investigated in acetonitrile solution by nanosecond laser photolysis at room temperature. In degassed solution, a short-lived transient (5 μs) has been identified as the triplet state of the closed spiro form. The ratio between the singlet and triplet pathways of ring opening has been determined from oxygen quenching measurements. In the presence of Co(II), UV irradiation is needed to induce the complexation. The fast second order rate constant for the 1:1 complex formation has been determined. It is suggested that such kinetic parameter could be used to characterise the properties of metallochromic spiropyrans.

Anatoliy BURLOV (h=13) 1. Dorokhov, A.V., Chernyshov, D.Yu., Burlov, A.S., Garnovskii, A.D., Ivanova, I.S., Pyatova, E.N., Tsivadze, A.Yu., (...), Chernyshev, V.V. Synchrotron powder diffraction in a systematic study of 4′-[2-(tosylamino)benzylideneamino]-2,3-benzo-15-crown-5 complexes, Acta Crystallographica Section B: Structural Science, 2007, 63 (3), pp. 402-410 (IF= 1.558)ABSTRACT: The crystal structures of two compounds, CuL2 and LiNCS·HL [HL = 4'-[2-(tosylamino)benzylideneamino]-2,3-benzo-15-crown-5], have been determined from synchrotron powder diffraction data. Both compounds crystallize in the monoclinic space group P21/c and with one molecule in the asymmetric unit. In CuL2 the four N atoms of two bidentate L ligands coordinate the CuII ion in a distorted tetrahedral geometry with Cu-N distances of 1.98 (5)-2.05 (5) Å, while two O atoms from two sulfoxide groups complete the distorted octahedral Cu coordination [Cu-O 2.64 (4), 2.74 (4) Å]. In LiNCS·HL, lithium is coordinated by all five ether O atoms with Li-O distances of 2.03 (3)-2.50 (3) Å and an N atom from the thiocyanate moiety [Li-N 1.98 (3) Å] in a distorted pentagonal pyramidal geometry. Preliminary potentiometric selectivity measurements for ion-selective electrodes (ISEs) based on CuL2 and ZnL2 demonstrated significant differences in their selectivity. In order to find a possible reason for this, theoretical calculations at the DFT (B3LYP) level were performed. These calculations used the crystal structures of CuL2, LiNCS·HL, ZnL2 and HL as input geometries for the minimum energy optimization in vacuo. The results indicate that in ML2 complexes (M = Cu, Zn) the electronic structure of the metal ion determines the spatial orientation of benzo-15-crown-5 macrocycles, and their different orientation in CuL2 and ZnL2 results in different potentiometric selectivities of ISEs based on these compounds.2. Burlov, A.S., Koshchienko, Y.V., Lyssenko, K.A., Vasilchenko, I.S., Alexeev, Y.E., Borodkina, I.G., Antipin, M.Yu., Garnovskii, A.D. Self-assembling tetranuclear complexes of a tridentate Schiff base, Journal of Coordination Chemistry, 2008, 61 (1), pp. 85-91 (IF= 1.547)ABSTRACT: A tetranuclear KZn3 complex consisting of three tridentate dibasic N2O donor ligands (derived from mono-N-phenyl-substituted 5-nitro-o-phenylenediamine) and one methylato group has been synthesized. Single-crystal multi-temperature (100–350K) X-ray diffraction studies of the complex reveal that {[ZnL]3OMe}− units are assembled by K…ON2 contacts into layers. Mutual position of the KO6 and {[ZnL]3OMe}− fragments of neighboring layers is temperature dependent.3. Burlov, A.S., Lyssenko, K.A., Koshchienko, Y.V., Nikolaevskii, S.A., Vasilchenko, I.S., Garnovskii, D.A., Uraev, A.I., Garnovskii, A.D. Mixed-ligand azomethine-benzimidazole palladium complex, Mendeleev Communications, 2008, 18 (4), pp. 198-199 (IF=0.901)ABSTRACT: An unusual palladium complex simultaneously containing azomethine and benzimidazole ligands was isolated after template reaction of o-tosylaminobenzaldehyde, 2-butylamino-5-nitroaniline and palladium diacetate and its structure was determined by X-ray diffraction analysis.4. Burlov, A.S., Antsyshkina, A.S., Sadikov, G.G., Koshchienko, Y.V., Divaeva, L.N., Mashchenko, S.A., Uraev, A.I., (...), Garnovskii, A.D. Direct chemical and electrochemical syntheses of coordination compounds of benzazolyl azo ligands, Journal of Coordination Chemistry, 2010, 63 (6) , pp. 917-930 (IF= 1.547)ABSTRACT: The chelates of 2-hydroxy(aminophenylnaphthyl)-azo-1-alkylbenzimidazoles were obtained from electrochemical (anodic dissolution of zero-valent d-metals) and chemical (from acetates of the same

metals) syntheses in methanol. The EXAFS and X-ray single crystal diffraction data revealed the existence of octahedral nickel, zinc, and cadmium complexes containing four five-membered metallocycles with the N4О2 or N6 ligand environments. The formation of five-membered coordination units, non-typical for azo ligands, is explained on the basis of inner-chelate competitive metal binding of ambidentate ligand systems.5. Burlov, A.S., Antsyshkina, A.S., Sadikov, G.G., Zubenko, A.A., Mashchenko, S.A., Vasilchenko, I.S., Sergienko, V.S., (...), Minkin, V.I. The first polymeric pentacoordinate zinc(II) azoimidazole complex, Mendeleev Communications, 2011, 21 (2), pp. 87-88 (IF=0.901)ABSTRACT: Coupling of 4,5-dichloro-2-phenyldiazenyl-1H-imidazole with zinc acetate gives rise to polymeric pentacoordinate Znii complex, whose structure was determined by X-ray diffraction study.6. Khimich, M.N., Popov, L.D., Burlov, A.S., Uzhinov, B.M. Excited state intramolecular proton transfer in o-tosylaminobenzaldehyde, Journal of Fluorescence, 2012, 22 (4), pp. 1095-1100 (IF=2.107)ABSTRACT: Dynamics of excited-state intramolecular proton transfer (ESIPT) in o-tosylaminobenzaldehyde has been studied by femtosecond absorption spectroscopy with a time resolution of 30 fs. The characteristic time of this process is ∼100 fs. Differential absorption rate curves exhibit oscillations that are consistent with theoretically predicted ESIPT-promoting vibrational modes. Efficient nonradiative deactivation with a rate constant of 6.25 × 1010 s−1 occurs in the excited product of proton transfer, with internal rotation followed by intersystem crossing being one of the feasible deactivation pathways.7. M. N. Khimich, V. A. Nadtochenko, L. D. Popov, A. S. Burlov, V. L. Ivanov, N. N. Denisov, F. E. Gostev, I. V. Shelaev, O. M. Sarkisov, B. M. Uzhinov Femtosecond dynamics of excited-state intramolecular proton transfer in o-tosylaminobenzaldehyde, High Energy Chemistry, 2012, 46 (4), pp. 247-252 (IF=0.815)ABSTRACT: Dynamics of excited-state intramolecular proton transfer (ESIPT) in o-tosylaminobenzaldehyde has been studied by femtosecond absorption spectroscopy with a time resolution of 30 fs. The characteristic time of this process is ∼100 fs. Differential absorption rate curves exhibit oscillations that are consistent with theoretically predicted ESIPT-promoting vibrational modes. Efficient nonradiative deactivation with a rate constant of 6.25 × 1010 s−1 occurs in the excited product of proton transfer, with internal rotation followed by intersystem crossing being one of the feasible deactivation pathways. Tatyana GRIBANOVA (h=11)1. T.N. Gribanova, R.M. Minyaev and V.I. Minkin, Planar hexacoordinated boron in organoboron compounds: ab initio study. Mendeleev Commun., 2001,N5, p.169-170. (IF=0.901)ABSTRACT: Ab initio [MP2(fu)/6-31G**, MP2(fu)/6-311G**] and DFT [B3LYP/6-31G**, B3LYP/6-311G**] calculations predict stable planar structures of the nonclassical compounds BB6(CH)3 and BB6X2− (X = NH, O) containing a hexacoordinated central boron atom.2. Tatyana N. Gribanova, Ruslan M. Minyaev, and Vladimir I. Minkin. A planar tetracoordinate nitrogen in boron-containing compounds: theoretical quantum-chemical study, Mendeleev Commun., 2002, №5, р.170-172. (IF=0.901)ABSTRACT: A series of stable non-classical structures of boron-containing compounds with planar tetracooordinate nitrogen atoms has been computationally designed based on density functional theory [B3LYP/6-311+G(d,p)] calculations.3. R.M. Minyaev, V.I. Minkin, T.N. Gribanova, A.G. Starikov, R. Hoffmann. "Poly[n]prismanes. A Family of Stable Cage Structures with Half-Planar Carbon Centers". J. Org. Chem., 2003, 68 (22), 8588-8593. (IF= 4.450)ABSTRACT: A series of bi[n]prismanes and tri[n]prismanes (n = 3−6) containing n and 2n, respectively, tetracoordinated carbon centers with nonclassical bisphenoidal (half-planar) configuration has been designed computationally.4. Ruslan M. Minyaev, Vladimir I. Minkin and Tatyana N. Gribanova, Carbon sandwich compounds: a quantum-chemical study. Mendeleev Commun., 2004, N3, pp.96-98. (IF=0.901)

ABSTRACT: Ab initio [MP2(fu)/6-311+G**] and DFT (B3LYP/6-311+G**) calculations predict highly symmetrical stable structures of sandwich compounds with a central carbon atom between three-, four- and five-membered (BH)n rings.5. Belkova N.V., Gribanova T.N., Gutsul E.I., Minyaev R.M., Bianchini C., Peruzzini M., Zanobini F., Shubina E.S., Epstein L.M. Specific and non-specific influence of the environment on dihydrogen bonding and proton transfer to [RuH2{P(CH2CH2PPh2)3}]. J Mol. Struct., 2007, vol. 844 – 845, pp. 115 – 131. (IF=1.634)ABSTRACT: The proton transfer from substituted phenols (ArOH = p-nitrophenol, p-nitophenyl-aza-phenol) to the ruthenium dihydride complex [(PP3)RuH2], where PP3 = P(CH2CH2PPh2)3, was studied by variable temperature UV–visible spectroscopy in dichloromethane, THF, THF/CH3OH and THF/CH3CN mixtures, showing a significant influence of the polarity and/or the proton donating/proton accepting properties of the solvent on the position of the proton transfer equilibrium. The formation of ion pairs stabilized by hydrogen bonding between the non-classical cation [(PP3)RuH(η2-H2)]+ and the homoconjugated anion [ArOHOAr]− was determined in low-polar media. The increase of the media polarity has been proved to favor the proton transfer leading to the dissociation of hydrogen bonded ion pairs [{(PP3) RuH(η2-H2)}+⋯{ArOHOAr}−]. Under comparable media polarity, the presence of a protic solvent in the mixture greatly favors the proton transfer due to the additional H-bonding with solutes. The structural, energetic and electronic features of the dihydrogen bonded adducts and of the proton transfer products were investigated by means of DFT/B3LYP calculations on the model dihydride [{P(CH2CH2PH2)3}RuH2] using CH3OH or CF3OH as proton donors. The specific and non-specific influence of the media properties on the dihydrogen bonding and proton transfer was studied by introducing the second protic (proton donor or solvent) molecule in the model system or by CPCM calculations. The additional participation of external molecules, from either the solvent or the alcohol, strengthens remarkably the dihydrogen bonded adducts and eases the proton transfer process.6. Gribanova T.N., Minkin V.I., Minyaev R.M. A theoretical approach to study and design of prismane systems. In: Strained Hydrocarbons. Ed. Dodziuk H. WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, 2008.7. Tatyana N. Gribanova, Andrey G. Starikov, Ruslan M. Minyaev, and Vladimir I. Minkin Matthew R. Siebert, and Dean J. Tantillo. Sandwich compounds of transition metals with cyclopolyenes and isolobal boron analogues. Chem. Eur.J., 2010, v.16, p.2272-2281 (IF= 5.382)ABSTRACT: A series of sandwich compounds of transition metals (M=Ni, Fe, Cr) with cyclic hydrocarbon (M(CH)n) and borane (M(BH2)n), ligands (including mixed hydrocarbon/borane sandwiches) has been studied using density functional theory (B3LYP/6-311+G(df,p)). Multicenter bonding between the central metal atom and basal cycloborane rings provides stabilization to planar cycloborane species. Large negative NICS values allude to aromatic character in the cycloboranes similar to the analogous cyclic hydrocarbons. The ability of cycloborane sandwiches to stabilize attached carbocations, radicals and carbanions is also assessed.8. Tatyana N. Gribanova, Ruslan M. Minyaev, and Vladimir I. Minkin, Induced Aromaticity and Electron-Count Rules for Bipyramidal and Sandwich Complexes of s- and d-Metals. Aromaticity, The Open Organic Chemistry Journal, 2011, - Volume 5, pp.62-78 (ISSN: 1874-0952), Bentham Science Publishers, Bussum, Netherlands.ABSTRACT: Structures and stability of an extended series of bipyramidal, sandwich and sandwich-bipyramidal mixed complexes formed by conjugated cyclic hydrocarbons (CH)n with s- (Li, Na, K, Be, Mg, Ca) and d- (Cr, Mn, Fe) metals have been studied using DFT B3LYP/6-311+G(df,p) calculations. Stable structures of the compounds satisfy a general (6n + 6d + 12c) electron-count rule, where n stands for total number of the basal hydrocarbon rings, d is total number of d-metal centers (or separate sandwich moieties) and c is total number of apical metal-carbonyl groups. It is shown that stabilization of the studied polyhedral organometallic structures (induced aromaticity) is caused by filling 6π-electronic shells of basal (4-6)-membered cycles provided by donation of additional electrons from metal centers thereby acquiring closed 18-electron shells.9. Tatyana N. Gribanova, Ruslan M. Minyaev, and Vladimir I. Minkin, Multidecker tricarbonyl-bridged sandwich complexes of transition metals: structure, stability and electron-counting rules, Physical

Chemistry Chemical Physics, 2012, 14, 14803-14809 - Royal Society of Chemistry, Thomas Graham House, Science Park, Milton Road, Cambridge CB4 (DOI:10.1039/C2CP41839H. (IF= 3.573)10. Tatyana N. Gribanova, Nikolay S. Zefirov and Vladimir I. MinkinStructure and stability of the heteroannulated [8–10]circulenes: A quantum-chemical study Pure Appl. Chem., 2010, Vol. 82, No. 4, pp. 1011-1024 (IF= 2.789)ABSTRACT: The structure and stability of a new family of heterocyclic [n]circulenes CnNnYn (n = 8–10; Y = N, P, As, BF2, AlF2, GaF2) have been computationally studied using density functional theory (DFT) B3LYP/6-311G* calculations. The geometry of the compounds is determined by the balance of steric factors and effects of aromatic π-electron delocalization depending on the electronegativity of heteroatoms. An increase in the bulkiness of peripheral atoms Y and enlargement of the inner Cn cycle leads to the gradual transformation of the bowl-shaped circulene structure (Y = N, BF2) to planar and then saddle-shaped forms (Y = P, As, AlF2, GaF2). The calculations performed manifest stabilization of the heteroannulated circulenes ensured by the strong aromatic character of the conjugated five-membered rings fringing the central non-aromatic or antiaromatic [8–10] annulene rings.

Valdimir BREN (h=16)1. Bren, V.A. Fluorescent and photochromic chemosensors, Russian Chemical Reviews, 2001, 70 (12), pp. 1017-1036 (IF=2.644)ABSTRACT: Data on organic chemosensors published over recent years are surveyed and described systematically. The bibliography includes 165 references.2. A.D. Dubonosov, V.A. Bren, V.I. Minkin. The Photochemical Reactivity of the Norbornadiene- Quadricyclane System. In: Organic Photochemistry and Photobiology (Eds.W. Horspool, F. Lenci). Ch. 17, 1-34.CRC Press. Boca Raton-London-New York. 2004. 3. Bren, V.A., Dubonosov, A.D., Popova, L.L., Rybalkin, V.P., Sadekov, I.D., Shepelenko, E.N., Tsukanov, A.V. Photochromic properties of 2-(N-acetyl-N-arylaminomethylene) benzo[b]furan-, thiophene-, selenophene- and tellurophene-3(2H)-ones, Arkivoc, 2005 (7), pp. 60-66 (IF = 1.252) ABSTRACT: Novel photochromic systems – (2Z)-2-(N-acetyl-N-arylaminomethylene)benzo[b]tellurophene-3(2H)-ones have been synthesized. Their properties were studied in comparison with analogous benzo[b]furan, benzo[b]thiophene, and benzo[b]selenophene derivatives. The long-wave absorption band of these compounds shifts bathochromically in the following order of heteroatoms: O < S < Se < Te from 380 nm to 455 nm and the quantum yields of photoinitiated N→O acyl rearrangement (including Z/E-isomerization around the C=C bond and fast thermal migration of the acetyl group) increase from 0.60 (S) to 0.71 (Te). The acid catalyzed reverse O→N acyl rearrangement constant rates are 1.1 · 10-4 s-1 (Te) < 4.2 10-4 s-1 (Se) < 1.0 10-3 s-1 (S).4. Bren, V.A., Dubonosov, A.D., Minkin, V.I., Tsukanov, A.V., Gribanova, T.N., Shepelenko, E.N., Revinsky, Y.V., Rybalkin, V.P. Photochromic crown-containing molecular switches of chemosensor activity Journal of Physical Organic Chemistry, 2007, 20 (11) , pp. 917-928 (IF = 1.963)ABSTRACT: The crown-ether functionalized 2-(N-acetyl-N-arylaminomethylene)benzo[b]thiophene-3(2H)-ones exhibit photochromic behavior involving photoinitiated Z/E-isomerization around the exocyclic CC bond followed by a fast thermal N → O acetyl migration and syn → anti isomerization of the resulting kinetically stable O-acetyl isomers. The reverse rearrangement is an acid catalyzed reaction. The addition of alkali-earth metal ions to solutions of N-acyl isomers induces negligible changes in their UV/Vis spectra, which can be significantly enhanced after irradiation and conversion to the O-acyl isomers. The compounds obtained may be used as sensitive photodynamic chemosensors with the ‘off-on’ mechanism for alkali-earth ions (Ca2+, Ba2+). Quantum-chemical calculations using the DFT B3LYP/LanL2DZ method predict greater affinity of these sensors to Ca2+ ions (in the gas phase) and to Ba2+ ions (in acetonitrile). 5. Minkin, V.I., Dubonosov, A.D., Bren, V.A., Tsukanov, A.V. Chemosensors with crown ether-based receptors, Arkivoc 2008 (4) , pp. 90-102 (IF = 1.252) ABSTRACT: The review highlights the rational design of crown ether-based optical chemosensors that are categorized according to the origin of the signaling unit as chromogenic, fluorogenic, photoswitchable, ambidentate and ditopic. The principal mechanisms that govern the properties of crown ether-based

chemosensors of different types are considered and examples of the detection of alkali, alkali-earth, d-metal, lanthanide cations, anions and molecules are given.6. Rybalkin, V.P., Popova, L.L., Tsukanov, A.V., Dubonosov, A.D., Bren', V.A., Minkin, V.I. N(O)-acylated 2-(N-phenylaminomethylene)benzo[b]thiophene-3(2H)-ones as molecular switches with a variable migrant, High Energy Chemistry, 2008, 42 (7) , pp. 606-609 (IF = 0.815)7. Nikolaeva, O.G., Tsukanov, A.V., Shepelenko, E.N., Lukyanov, B.S., Metelitsa, A.V., Kostyrina, O.Y., Dubonosov, A.D., Vladimir A. Bren, Minkin, V.I. Synthesis of novel iono- and photochromic spiropyrans derived from 6,7-dihydroxy-8-formyl-4-methyl-2H-chromene-2-one, International Journal of Photoenergy, 2009 , art. no. 238615 (IF=1.769)ABSTRACT: Novel photochromic spiropyrans (SPPs) containing -hydroxy group were synthesized and their spectral properties as well as abilities for complexation with metal ions studied. In solutions they exist as equilibrium mixture of spirocyclic (A) and merocyanine (B) isomers. The largest content of merocyanine form was found for the derivative with an electron-donating methyl group in position 5 of hetaryl fragment. The irradiation of SPPs in acetonitrile shifts the equilibrium to the B form. Similar effect causes the addition of metal cations due to formation of colored complexes with merocyanine isomers.8. Minkin, V.I., Tsukanov, A.V., Dubonosov, A.D., Bren, V.A. Tautomeric Schiff bases: Iono-, solvato-, thermo- and photochromism Journal of Molecular Structure, 2011, 998 (1-3), pp. 179-191 (IF = 1.634)ABSTRACT: The review article summarizes the recent data about novel tautomeric iono-, solvato-, thermo- and photochromic Schiff bases. This contribution focuses on the factors determining tautomeric equilibrium and on the investigations into the proton transfer mechanisms.

Andrey STARIKOV (h=10)1. Minyaev R.M., Starikov A.G., Minkin V.I. Stabilization of the glycine zwitterionic form by complexation with Na+ and Cl-: an ab initio study. // Mendeleev Commun. 2000. v.10. p. 43-44. (IF=0.901)ABSTRACT: Ab initio [MP2(full)/6-31G**] calculations predict that the glycine zwitterionic form bridged with NaCl is more stable than the isomeric complexes of the neutral forms2. Sadekov, I.D., Minkin, V.I., Zakharov, A.V., Starikov, A.G., Borodkin, G.S., Aldoshin, S.M., Tkachev, V.V., Shilov G.V., Berry, F.J. Synthesis and structure of N-arylimines of β-tellurocyclohexenals with the intramolecular coordination N → Te bonds, Journal of Organometallic Chemistry, 2005, 690 (1) , pp. 103-116 (IF=2.384)ABSTRACT: A series of N-arylimines of β-tellurocyclohexenals 11 have been synthesized and the molecular and crystal structures of the compounds 11a-e and also β-(dimethyltelluronium)cyclohexenal perchlorate 12 studied by X-ray crystallography. All the compounds contain strong intramolecular coordination N → Te (O → Te) bonds of the hypervalent type. In 11a-e, the lengths of the N → Te bonds are within the range of 2.690-2.147 Å and are 1.0-1.5 Å shorter than the sum of the van der Waals radii of respective atoms. In the N-arylimines 11b-e with the electronegative groups attached to the tellurium center, the lengths of the N → Te bonds are very close to that characteristic of a standard covalent N-Te bond. The experimental observed geometries are well reproduced by the DFT calculations performed at B3LYP/LanL2DZ level of approximation. The energies of the intramolecular coordination N → Te bonds vary from 23 kJ mol -1 for 11a to 119 kJ mol -1 for 11e. The calculated energy of the O → Te bond in 12 was found to be 50 kJ mol -1. The 125Te NMR chemical shifts of compounds 11 span the wide range of 734.3-1622.4 ppm. The largest downfield 125Te NMR chemical shifts are observed in the case of the compounds 11e, f in which the most electronegative atoms are attached to the tellurim centers.. 3. Starikov, A.G., Minyaev, R.M., Minkin, V.I. Theoretical modeling of the square-planar to tetrahedral isomerization of bis-chelate nickel(II) complexes, Chemical Physics Letters, 2008, 459 (1-6) , pp. 27-32 (IF=2.337) ABSTRACT: The B3LYP/6-311++G(d,p) calculations of square-planar to tetrahedral conformational isomerization of bis-(propane-1,3-dionato)Ni(II) I and bis-(N-methyl-oxyvinylaldiminato)Ni(II) II complexes have been performed and the energy profiles for the low-energy barrier spin crossover rearrangements have been evaluated. The transitions between two forms of the complexes occur via the minimal energy crossing points (MECP) located at the intersection of the lowest singlet and triplet PESs.

The calculated relative energies of the MECPs (7.0 and 7.1 kcal mol-1) correspond to the estimated energy barriers to the conformational isomerizations of I and II. 4. Starikov, A.G., Minyaev, R.M., Minkin, V.I. Theoretical modeling of enantiomerization mechanisms of tetrahedral bis-(β-diiminato) Ni(II) complexes, Journal of Molecular Structure: THEOCHEM, 2009, 895 (1-3) , pp. 138-141 (IF=1.437)ABSTRACT: The mechanism for the low-energy barrier degenerate enantiomerization (enantiotopomerization) of bis-chelate tetrahedral six-membered ring bis-(ОІ-dialdiminato) Ni(II) complexes has been studied by applying DFT B3LYP/6-311++G(d, p) method to a model system of bis-[methyl-3-(methylimino)-prop-1-enyl)-amino] Ni(II). The energy preferred reaction path involves a spin crossover step via the minimal energy crossing points (MECP) located at the intersection of the lowest singlet and triplet PESs. The calculated energy barrier (18.6 kcal mol-1) is in a good agreement with the available experimental data. 5. Starikov, A.G., Minyaev, R.M., Minkin, V.I. Theoretical modeling of the molecular and crystal structures and a square-planar to tetrahedral conformational rearrangement of trans-planar bis(N-methylsalicylaldiminato)nickel(II), Mendeleev Communications, 2009, 19 (2) , pp. 64-66 (IF=0.901)ABSTRACT: The DFT B3LYP/6-311++g(d,p)/6-31g(d,p) calculations performed on bis(N-methylsalicylaldiminato)nickel(II), its isomers and clusters containing up to ten molecules of the complex have shown that the metal chelate rings are intrinsically planar and their step-like distortion observed in the solid state is caused by the factors relevant to the crystal packing conditions. 6. Starikov, A.G., Minkin, V.I., Minyaev, R.M., Koval, V.V.A quantum chemical study of bis-(iminoquinonephenolate) Zn(II) complexes(2010) Journal of Physical Chemistry A, 114 (29), pp. 7780-7785. (IF=2.946)ABSTRACT: A computational DFT B3LYP*/6-311++G(d,p) study performed on bis-(iminoquinonephenolate) Zn(II) complex [ZnII(C12H 8NO2)2] has revealed a previously unexplored mechanism for valence tautomerism inherent in transition metal complexes with redox active (noninnocent) ligands. The occurrence of energy-close isomeric forms of the complex and their low energy barrier interconversion is caused not by the intramolecular electron transfer (IET) between the metal and ligand frontier orbitals, but the intersystem conversion within a redox active ligand without involvement of a metal center. This mechanism gives a new insight into the origin of the previously experimentally studied isomeric forms of bis-(iminoquinonephenolate) Zn(II) complexes that must be assigned to [Zn II(1L-1)2] (8) and [Zn II(1L-1)(3L-1)] (9) structures. The spin-forbidden transition between the two forms of the complex proceeds via a minimal energy crossing point (MECP) corresponding to the energy barrier of 8.9 kcal mol-1 for the 9 → 8 transformation in the gas phase. 7. Ivakhnenko, E.P., Starikov, A.G., Minkin, V.I., Lyssenko, K.A., Antipin, M.Y., Simakov, V.I., Korobov, M.S., Borodkin, G.S., Knyazev, P.A. Synthesis, molecular and electronic structures of six-coordinate transition metal (Mn, Fe, Co, Ni, Cu, and Zn) complexes with redox-active 9-hydroxyphenoxazin-1-one ligands, Inorganic Chemistry, 2011, 50 (15), pp. 7022-7032 (IF=4.601) ABSTRACT: A series of pseudo-octahedral metal (M = Mn, Fe, Co, Ni, Cu, Zn) complexes 4 of a new redox-active ligand, 2,4,6,8-tetra(tert-butyl)-9-hydroxyphenoxazin-1- one 3, have been synthesized, and their molecular structures determined with help of X-ray crystallography. The effective magnetic moments of complexes 4 (M = Mn, Fe, Co, and Ni) measured in the solid state and toluene solution point to the stabilization of their high-spin electronic ground states. Detailed information on the electronic structure of the complexes and their redox-isomeric forms has been obtained using density functional theory (DFT) B3LYP*/6-311++G(d,p) calculations. The energy disfavored low-spin structures of manganese, iron, and cobalt complexes have been located, and based on the computed geometries and distribution of spin densities identified as Mn IV[(Cat-N-SQ)] 2, Fe II[Cat-N-BQ)] 2, and Co II[Cat-N-BQ)] 2 compounds, respectively. It has been shown that stabilization of the high-spin structures of complexes 4 (M = Mn, Fe, Co) is caused by the rigidity of the molecular framework of ligands 3 that sterically inhibits interconversions between the redox-isomeric forms of the complexes. The calculations performed on complex 4 (M = Co) predict that a suitable structural modification that might provide for stabilization of the low-spin electromeric forms and create conditions for the valence tautomeric rearrangement via

stabilization of the low-spin electromer and narrowing energy gap between the low-spin ground state tautomer and the minimal energy crossing point on the intersection of the potential energy surfaces of the interconverting structures consists in the replacement of an oxygen in the oxazine ring by a bulkier sulfur atom.

Aleksandr DUBONOSOV (h=10)1. Dubonosov, A.D., Bren, V.A., Chernoivanov, V.A. Norbornadiene-quadricyclane as an abiotic system for the storage of solar energy, Russian Chemical Reviews, 2002, 71 (11) , pp. 917-927 (IF = 2.644)ABSTRACT: Data on the valence isomerisation of norbornadiene and its derivatives into the corresponding quadricyclanes published between 1990 and 2001 are considered and described systematically. The applicability of this reaction for the storage of solar energy is discussed. The bibliography includes 112 references.2. Dubonosov, A.D., Minkin, V.I., Bren, V.A., Popova, L.L., Rybalkin, V.P., Shepelenko, E.N., Tkalina, N.N., Tsukanov, A.V. Photochromic 2-(N-acyl-N-arylaminomethylene)benzo[b]thiophene-3(2H)-oneswith fluorescent labels and/or crown-ether receptors, Arkivoc 2003 (13) , pp. 12-20 (IF = 1.252)ABSTRACT: Novel N-acylaminovinyl ketones of the benzo[b]thiophene series (AAB) capable of molecular switching of fluorescence or complexation with metal ions have been synthesized and their photochromic behavior studied using UV-Vis absorption/emission and 1H- / 7Li- NMR spectroscopy. Under UV irradiation the AAB compounds 2a–c containing fluorescent labels as their N-aryl substituents undergo Z/E- photo-isomerization and N→O acyl rearrangement resulting in the formation of O-acyl isomers 3a–c. The photo-switching of fluorescence has been found in the 4-fluorenonyl derivative 2a. The benzo-15-crown-5- containing AAB 2d,e are also susceptible to the same type of photo-initiated rearrangement. The corresponding O-acyl isomers 3d–e represent a group of chemosensors which readily form stable complexes with alkali- and alkali-earth- metal cations. The AAB 2d exhibits specific selectivity for Li+ ion in the presence of Na+, K+ and Cs+.3. Dubonosov, A.D., Minkin, V.I., Bren, V.A., Shepelenko, E.N., Tsukanov, A.V., Starikov, A.G., Borodkin, G.S. Tautomeric crown-containing chemosensors for alkali-earth metal cations Tetrahedron, 2008, 64 (14), pp. 3160-3167 (IF = 3.025)ABSTRACT: Crown-containing arylimines of 5-hydroxy- and 5-hydroxy-6-nitro-2,3-diphenylbenzo[b]furan-4-carbaldehydes were synthesized and their structure, spectral, luminescent, and complexing properties were studied by means of 1H and 13C NMR, IR, UV, and mass-spectrometry. In solution, these compounds exist as equilibrium mixtures of benzenoid and quinoid tautomers. The relative concentration of the quinoid form increases in the order of solvents: toluene, acetonitrile, 2-propanol, chloroform. The presence in the benzo[b]furan moiety of a strong withdrawing 6-NO2 group favors stabilization of the quinoid tautomer. This finding is in accord with the results of the DFT B3LYP/6-311++g(d,p) calculations. Complexation of 5-hydroxy-6-nitro-2,3-diphenyl-1-benzofuran-4-carbaldehyde crown-containing imines with alkali and alkali-earth metal ions shifts the tautomeric equilibrium to the quinoid forms and is accompanied by blue shifts of the emission spectra. The Schiff bases obtained represent a new type of fluorescent tautomeric chemosensor for Mg2+, Ca2+ (benzo-15-crown-5 derivative), and Ba2+ (benzo-18-crown-6 derivative) displaying diagnostic changes in both absorption and emission spectra.4. Minkin, V.I., Dubonosov, A.D., Bren, V.A., Tsukanov, A.V. Chemosensors with crown ether-based receptors, Arkivoc 2008 (4) , pp. 90-102 (IF = 1.252)ABSTRACT: The review highlights the rational design of crown ether-based optical chemosensors that are categorized according to the origin of the signaling unit as chromogenic, fluorogenic, photoswitchable, ambidentate and ditopic. The principal mechanisms that govern the properties of crown ether-based chemosensors of different types are considered and examples of the detection of alkali, alkali-earth, d-metal, lanthanide cations, anions and molecules are given.5. Nikolaeva, O.G., Tsukanov, A.V., Shepelenko, E.N., Lukyanov, B.S., Metelitsa, A.V., Kostyrina, O.Y., Dubonosov, A.D., Vladimir A. Bren, Minkin, V.I. Synthesis of novel iono- and photochromic spiropyrans derived from 6,7-dihydroxy-8-formyl-4-methyl-2H-chromene-2-one, International Journal of Photoenergy, 2009 , art. no. 238615 (IF=1.769)

ABSTRACT: Novel photochromic spiropyrans (SPPs) containing -hydroxy group were synthesized and their spectral properties as well as abilities for complexation with metal ions studied. In solutions they exist as equilibrium mixture of spirocyclic (A) and merocyanine (B) isomers. The largest content of merocyanine form was found for the derivative with an electron-donating methyl group in position 5 of hetaryl fragment. The irradiation of SPPs in acetonitrile shifts the equilibrium to the B form. Similar effect causes the addition of metal cations due to formation of colored complexes with merocyanine isomers.6. Dubonosov, A.D., Rybalkin, V.P., Popova, L.L., Tsukanov, A.V., Revinsky, Y.V., Bren, V.A., Minkin, V.I. Acylated 2-(N-arylaminomethylene)benzo[b]thiophene-3(2H)-Ones: Molecular switches with varying migrants and substituents, International Journal of Photoenergy 2009 , art. no. 694196 (IF = 1.769) ABSTRACT: Synthesis and properties of photochromic acylated 2-(-arylaminomethylene)benzo[]thiophene-3(2)-ones are described. Their structure largely depends on the nature of acyl migrant and in a less degree on N-aryl substituent. 7. Minkin, V.I., Tsukanov, A.V., Dubonosov, A.D., Bren, V.A. Tautomeric Schiff bases: Iono-, solvato-, thermo- and photochromism Journal of Molecular Structure, 2011, 998 (1-3) , pp. 179-191 (IF = 1.634)ABSTRACT: The review article summarizes the recent data about novel tautomeric iono-, solvato-, thermo- and photochromic Schiff bases. This contribution focuses on the factors determining tautomeric equilibrium and on the investigations into the proton transfer mechanisms.

Gennadiy BORODKIN (h=9)1. Ukhin, L.Y., Suponitsky, K.Y., Shepelenko, E.N., Belousova, L.V., Borodkin, G.S. Novel synthesis of oxonine derivatives from 3-[(2-aminophenyl)amino]-5,5- dimethyl-2-cyclohexene-1-one and o-quinones Tetrahedron Letters, 2012, 53 (1) , pp. 67-70 (IF = 2.683) ABSTRACT: A new method for the synthesis of hitherto unreported 9-membered macrolactones by reaction of 3-[(2-aminophenyl)amino]-5,5-dimethyl-2-cyclohexen-1-one with o-quinones in the presence of acidic catalysts is presented.2. Suzdalev, K.F., Den'Kina, S.V., Borodkin, G.S., Tkachev, V.V., Kiskin, M.A., Kletsky, M.E., Burov, O.N. Reaction of 2-chloroindole-3-carbaldehyde with epihalogenohydrins. Tandem oxirane-opening - 1,3-oxazole-closure process Tetrahedron, 2011, 67 (45) , pp. 8775-8779 (IF = 3.025) ABSTRACT: Reaction of 2-chloroindole-3-carbaldehyde with epibromohydrin gives the expected 1-(oxiran-2-ylmethyl) derivative. However the analogous reaction with epichlorohydrin leads to the formation of the oxazolo[3,2-a]indole skeleton. Some chemical properties of this tricyclic system were investigated. Its reaction with secondary amines unexpectedly proceeds with the opening of the oxazole ring.3. Ukhin, L.Y., Akopova, A.R., Bicherov, A.V., Kuzmina, L.G., Morkovnik, A.S., Borodkin, G.S. Reactions of Bunte salts with carbocations of isobenzofuranone and isoindolone Tetrahedron Letters, 2011, 52 (42) , pp. 5444-5447 (IF = 2.683) ABSTRACT: A convenient method for the preparation of functionalized derivatives of isobenzofuran-1(3H)-ones and isoindol-1(3H)-ones by reactions of their carbocations with Bunte salts is described. The reactions proceed by means of electrophilic attack on the S(II)-atom of the Bunte salts.4. Chernysh, 1. Tatarov, A., Kurbatov, S., Borodkin, G., Goumont, R., Terrier, F. S EAr-S NAr couplings of indolizines and related pyrrole derivatives with superelectrophilic nitrobenzoxadiazoles Tetrahedron, 2010, 66 (4) , pp. 995-1006 (IF = 3.025)ABSTRACT: The nucleophilic aromatic substitutions of 7-chloro-4,6-dinitrobenzofurazan (DNBZ-Cl) and 7-chloro-4,6-dinitrobenzofuroxan (DNBF-Cl) with a series of differently substituted indolizines (5a–f) and a series of dihyropyrroloisoquinolines (11a–f) have been investigated. In accord with previous reports emphasizing the superelectrophilic character of these compounds in σ-complexation processes, DNBZ-Cl and DNBF-Cl react very readily and quantitatively with the weak carbon nucleophiles 5a–f and 11a–f at room temperature in acetonitrile. In the case of DNBZ-Cl, the resulting products (7Z,a–f and 12Z,a–f) are those expected from the displacement of the chlorine atom through a SEAr–SNAr mechanism. A significant result is that these compounds, despite the lack of coplanarity of the two rings, are characterized by an intense intramolecular charge transfer between the donor pyrrole-type moiety and the electron-deficient acceptor DNBZ moiety. Contrasting with this behaviour, the DNBF-Cl reactions show a totally

different pattern, proceeding with loss of the N-oxide functionality and expansion of the pyrrole moiety to afford stable zwitterionic spiro adducts (8F,a–f and 13F,a–f) of a so far unknown type. Rapid NMR recordings have revealed that the formation of these adducts occurs after initial formation of the expected substitution products 7F,a–f and 12F,a–f. A mechanism accounting for the overall rearrangement leading to the spirobenzofurazan adducts is suggested. It is based on an initial nucleophilic attack of the oxygen atom of the N-oxide functionality at the electron-deficient and strongly olefinic C–C coupling bond generated by the aforementioned intramolecular charge transfer. This results in the formation of an unstable five-membered isoxazole ring whose decomposition goes along with loss of the N-oxide functionality and enlargement of the pyrrole moiety into a pyridine one. Also discussed are the factors accounting for the high thermodynamic stability of the spiro adducts, and their relevance to the stability of previously reported spiro adducts.5. Yu.E., Volynkin, V.A., Panyushkin, V.T., Kondakov, V.I., Korobov, M.S., Borodkin, G.S. The use of selective methods of heteronuclear NMR spectroscopy in studies of multicomponent systems Russian Chemical Reviews, 2005, 74 (4) , pp. 317-337 (IF = 2.644) ABSTRACT: Some important aspects of the use of selective methods in NMR spectroscopy for interpreting the spectra of complex multicomponent systems, measuring the spin–spin coupling constants and determining the structure of compounds are discussed. Procedures for recording selective spectra and the application of selective radiofrequency pulses together with magnetic field gradient pulses are described. Practical methods for suppression of water signals in the study of biological samples are considered.

Dmitriy GARNOVSKII (h=17) 1. Garnovskii, A.D., Sadimenko, A.P., Sadimenko, M.I., Garnovskii, D.A. Common and less-common coordination modes of the typical chelating and heteroaromatic ligands Coordination Chemistry Reviews, 1998, 173 (1) , pp. 31-77 (IF=12.110)ABSTRACT: Data on the different modes of bonding the metals to the most widely spread chelating [β-diketones, o-oxyazomethines, o-oxy(mercapto) derivatives of azoles and azines] and heteroaromatic ligands are generalized and systematized. It is shown that, besides the common β-diketonates, aldiminates, phenolates and mercaptophenolates structures, these complex compounds exhibit less-common modes of coordination. Five- and six-membered heterocycles form σ- as well as π-complexes.2. Kharisov, B.I., Garnovskii, D.A., Blanco, L.M., Burlov, A.S., Vasilchenko, I.S., Garnovskii, A.D. Direct electrochemical synthesis of novel transition metal chelates of tridentate azomethinic ligands, Polyhedron, 1999, 18 (7) , pp. 985-988 (IF=2.057)ABSTRACT: New chelates of the type ML(L1)n·MeOH (n=1, 2) were obtained on the basis of the tridentate azomethinic ligands 2-N-tosylamine(2′-hydroxybenzal)aniline (L) and 2-N-tosylamine(2′-tosylaminobenzal)aniline (L1) and zero-valent transition metals (Co, Ni, Cu, Zn, Cd) under electrosynthesis conditions. The mononuclear character of these products and the participation of N2O- or N3 groups of the azomethinic ligands in the coordination are demonstrated by IR, 1H NMR spectral and magnetic data (77–293 K).3. Garnovskii, D.A., Guedes da Silva, M.FátimaC., Pakhomova, T.B., Wagner, G., Duarte, M.Teresa, Fraústo da Silva, J.J.R., Pombeiro, A.J.L., Kukushkin, V.Yu. Iminoacylation Part 6: Coupling of chloro- and amidoximes Ar(R)C=NOH (R = Cl, NH 2) with acetonitrile ligands coordinated to platinum(IV), Inorganica Chimica Acta, 2000, 300-302 , pp. 499-504 (IF=1.846)ABSTRACT: Addition of chloro- and amidoximes RR1CNOH (R/R1=Cl/Ph, Cl/C6H4-p-Me, Cl/C6H4-p-NO2, NH2/Ph) to the acetonitrile ligands in trans-[PtCl4(MeCN)2] proceeds much slower as compared to ketoximes with donor substituents R/R1 [V.Yu. Kukushkin, T.B. Pakhomova, Yu.N. Kukushkin, R. Herrmann, G. Wagner, A.J.L. Pombeiro, Inorg. Chem. 37 (1998) 6511] and leads to the complexes with iminoacylated species [ligating (alkylideneaminooxy)imines] trans-[PtCl4{NHC(Me)ONCRR1}2]. X-ray crystal structure determination of two iminoacylated compounds (R/R1=Cl/C6H4-p-Me, Cl/C6H4-p-NO2) disclosed their overall trans geometry with monodentate organic ligands in E-conformation and indicated NH⋯N hydrogen bonding between the imino H atom and the oxime nitrogen.

4. Bokach, N.A., Kukushkin, V.Y., Kuznetsov, M.L., Garnovskii, D.A., Natile, G., Pombeiro, A.J.L. Direct addition of alcohols to organonitriles activated by ligation to a platinum(IV) center, Inorganic Chemistry, 2002, 41 (8) , pp. 2041-2053 (IF=4.601)ABSTRACT: Treatment of trans-[PtCl4(RCN)2] (R = Me, Et) with R‘OH (R‘ = Me, Et, n-Pr, i-Pr, n-Bu) at 45 °C in all cases allowed the isolation of the trans-[PtCl4{(E)-NHC(R)OR‘}2] imino ester complexes, while the reaction between cis-[PtCl4(RCN)2] and the least sterically hindered alcohols (methanol and ethanol) results in the formation of cis-[PtCl4{(E)-NHC(R)OR‘}2] (R/R‘ = Me/Me) or trans-[PtCl4{(E)-NHC(Et)OR‘}2] (R‘ = Me, Et), the latter being formed via thermal isomerization (ROH, reflux, 3 h) of the initially formed corresponding cis isomers. The reaction between alcohols R‘OH and cis-[PtCl4(RCN)2] (R = Me, R‘ = Et, n-Pr, i-Pr, n-Bu; R = Et; R‘ = n-Pr, i-Pr, n-Bu), exhibiting greater R/R‘ steric congestion, allowed the isolation of cis-[PtCl4{(E)-NHC(R)OR‘}{(Z)-NHC(R)OR‘}] as the major products. The alcoholysis reactions of poorly soluble [PtCl4(RCN)2] (R = CH2Ph, Ph) performed under heterogeneous conditions, directly in the appropriate alcohol and for a prolonged time and, for R = Ph, with heating led to trans-[PtCl4{(E)-NHC(R)OR‘}2] (R = CH2Ph, R‘ = Me, Et, n-Pr, i-Pr; R = Ph, R‘ = Me) isolated in moderate yields. In all of the cases, in contrast to platinum(II) systems, addition of R‘OH to the organonitrile platinum(IV) complexes occurs under mild conditions and does not require a base as a catalyst. The formed isomerically pure (imino ester)Pt(IV) complexes can be reduced selectively, by Ph3PCHCO2Me, to the corresponding isomers of (imino ester)Pt(II) species, exhibiting antitumor activity, without change in configuration of the imino ester ligands. Furthemore, the imino esters NHC(R)OR‘ can be liberated from both platinum(IV) and platinum(II) complexes [PtCln{NHC(R)OR‘}2] (n = 2, 4) by reaction with 1,2-bis(diphenylphosphino)ethane and pyridine, respectively. All of the prepared compounds were characterized by elemental analyses (C, H, N), FAB mass spectrometry, IR, and 1H, 13C{1H}, and 195Pt (metal complexes) NMR spectroscopies; the E and Z configurations of the imino ester ligands in solution were determined by observation of the nuclear Overhauser effect. X-ray structure determinations were performed for trans-[PtCl4{(E)-NHC(Me)OEt}2] (2), trans-[PtCl4{(E)-NHC(Et)OEt}2] (10), trans-[PtCl4{(E)-NHC(Et)OPr-i}2] (11), trans-[PtCl4{(E)-NHC(Et)OPr-n}2] (12), and cis-[PtCl4{(E)-NHC(Et)OMe}2] (14). Ab initio calculations have shown that the EE isomers are the most stable ones for both platinum(II) and platinum(IV) complexes, whereas the most stable configurations for the ZZ isomers are less stable than the respective EZ isomers, indicating an increase of the stability on moving from the ZZ to the EE configurations which is more pronounced for the Pt(IV) complexes than for the Pt(II) species.5. Luzyanin, K.V., Kukushkin, V.Yu., Kuznetsov, M.L., Garnovskii, D.A., Haukka, M., Pombeiro, A.J.L. Novel reactivity mode of hydroxamic acids: A metalla-pinner reaction, Inorganic Chemistry, 2002, 41 (11), pp. 2981-2986 (IF=4.601)ABSTRACT: The reaction between the nitrile complex trans-[PtCl4(EtCN)2] and benzohydroxamic acids RC6H4C(O)NHOH (R = p-MeO, p-Me, H, p-Cl, o-HO) proceeds smoothly in CH2Cl2 at 45 °C for 2−3 h (sealed tube) or under focused 300 W microwave irradiation for 15 min at 50 °C giving, after workup, good yields of the imino complexes [PtCl4{NHC(Et)ONC(OH)(C6H4R)}2] which derived from a novel metalla-Pinner reaction. The complexes [PtCl4{NHC(Et)ONC(OH)(C6H4R)}2] were characterized by elemental analyses (C, H, N), FAB mass spectrometry, and IR and 1H and 13C{1H} spectroscopies, and [PtCl4{NHC(Et)ONC(OH)(Ph)}2] (as the bis-dimethyl sulfoxide solvate), by X-ray single-crystal diffraction. The latter disclosed its overall trans-configuration with the iminoacyl species in the hydroximic tautomeric form in E-configuration which is held by NH···N hydrogen bond between the imine NH atom and the hydroximic N atom.6. Garnovskii, D.A., Guedes da Silva, M.F.C., Kopylovich, M.N., Garnovskii, A.D., Fraústo da Silva, J.J.R., Pombeiro, A.J.L. Electrochemical synthesis of adducts of 2-aminopyridine or methanol in metal chelates of a N,N,N-tridentate Schiff base ligand. X-ray crystal structures of the Ni(II) and Zn(II) derivatives, Polyhedron, 2003, 22 (10) , pp. 1335-1340 (IF=2.057)ABSTRACT: The electrochemical syntheses of series of novel adducts of 2-aminopyridine and methanol in Co(II), Ni(II), Cu(II) or Zn(II) chelates of the N,N,N-tridentate basic form of the Schiff base 2-N-tosylamino(2′-tosylaminobenzylidene)aniline (H2L), [M(L)L′] (M=Co, Ni, Zn, L′=2-aminopyridine; M=Cu, L′=CH3OH), were performed by using the corresponding metal as a sacrificial anode. The compounds were characterized by elemental analysis, IR spectroscopy, FAB mass spectrometry, 1H NMR

and magnetic measurements. The crystal structures of the Zn and Ni derivatives as well as of the Schiff base have been determined by X-ray diffraction. In the 2-aminopyridine complexes this ligand is bound to the metal through the endocyclic nitrogen whereas the aminogroup is involved in intramolecular NH⋯O hydrogen bonds with one of the tosyl SO2 groups.7. Garnovskii, D.A., Pombeiro, A.J.L., Haukka, M., Sobota, P., Kukushkin, V.Yu. Regioselective HON-addition of bifunctional hydrazone oximes to Pt(IV)-bound nitriles, Dalton Transactions, 2004, (7), pp. 1097-1103 (IF=3.838)ABSTRACT: Treatment of trans-[PtCl4(RCN)2] (R = Me, Et) with the hydrazone oximes MeC(NOH)C(R′)NNH2 (R′ = Me, Ph) at 45 °C in CH2Cl2 led to the formation of trans-[PtCl4{NHC(R)ONC(Me)C(R′)NNH2}2] (R/R′ = Me/Ph 1, Et/Me 2, Et/Ph 3) due to the regioselective OH-addition of the bifunctional MeC(NOH)C(R′)NNH2 to the nitrile group. The reaction of 3 and Ph3PCHCO2Me allows the formation of the Pt(II) complex trans-[PtCl2{NHC(Et)ONC(Me)C(Ph)NNH2}2] (4). In 4, the imine ligand was liberated by substitution with 2 equivalents of bis(1,2-diphenylphosphino)ethane (dppe) in CDCl3 to give, along with the free ligand, the solid [Pt(dppe)2]Cl2. The free iminoacyl hydrazone, having a restricted life-time, decomposes at 20–25 °C in about 20 h to the parent organonitrile and the hydrazone oxime. The Schiff condensation of the free NH2 groups of 4 with aromatic aldehydes, i.e. 2-OH-5-NO2-benzaldehyde and 4-NO2-benzaldehyde, brings about the formation of the platinum(II) complexes trans-[PtCl2{NHC(Et)ONC(Me)C(Ph)NNCH(C6H3-2-OH-5-NO2}2] (5) and trans-[PtCl2{NHC(Et)ONC(Me)C(Ph)NNCH(C6H4-4-NO2}2] (6), respectively, containing functionalized remote peripherical groups. Metallization of 5, which can be considered as a novel type of metallaligand, was achieved by its reaction with M(OAc)2·nH2O (M = Cu, n = 2; M = Co, n = 4) in a 1 ∶ 1 molar ratio furnishing solid heteronuclear compounds with composition [Pt] ∶ [M] = 1 ∶ 1. The complexes were characterized by C, H, N elemental analyses, FAB+ mass-spectrometry, IR, 1H, 13C{1H} and 195Pt NMR spectroscopies; X-ray structures were determined for 3, 4 and 5.8. Garnov̧skii, D.A., Bokach, N.A., Pombeiro, A.J.L., Haukka, M., Fraústo Da Silva, J.J.R., Kukushkin, V.Yu. Microwave-assisted and PdII-mediated nitrile-oxime coupling, European Journal of Inorganic Chemistry, 2005, (17), pp. 3467-3471 (IF=3.049)ABSTRACT: Refluxing PdCl2 with the ketoximes R1R2C=NOH (R1R2 = MeMe, MeEt, C5H10) in RCN (R = Me, Et, nPr, Ph) for 2–3 h results in precipitation of the oxime complexes [PdCl2(R1R2C=NOH)2], whereas further reflux of the reaction mixture for an additional 6–12 h leads to formation of the chelated species [PdCl2{NH=C(R)ON=CR1R2-κ2N}] (R/R1R2 = Me/MeMe 1; Et/MeMe 2; nPr/MeMe 3; Me/MeEt 4; Me/C5H105; Ph/MeMe 6) by a PdII-mediated coupling between the oximes and the nitriles; complexes 1–6 were isolated in the solid state in 60–75 % yields. The reaction time could be drastically reduced, to 15–30 min, when the system was additionally irradiated with microwaves (100 W, about 60 °C). Compounds 1–6 can also be obtained without isolation of the intermediate oxime complexes either by refluxing for 8–15 h or by microwave irradiation (100 W, about 60 °C) for 15–30 min. The formulation of 1–6 is based upon satisfactory C, H, and N elemental analyses, FAB mass spectrometry, and IR, 1H and 13C{1H} NMR spectroscopy, while the structures of 1·(Me2CO), 1·(CHCl3), 2·(H2O), and 6·½(H2O) were determined by X-ray single-crystal diffraction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)9. Garnovskii, D.A., Kukushkin, V.Yu. Metal-mediated reactions of oximes, Russian Chemical Reviews, 2006, 75 (2) , pp. 111-124 (IF=2.644)ABSTRACT: The published data on metal-mediated reactions of oximes are described systematically. The attention is focused on the reactions that serve as convenient methods for the synthesis of various organic compounds or models for the interpretation of the mechanisms of catalytic processes and the reactions resulting in new ligand systems.10. Luzyanin, K.V., Galanski, M., Kukushkin, V.Yu., Garnovskii, D.A., Pombeiro, A.J.L. Regioselective addition of bifunctional oximehydroxamic acid by the hydroxamic group to Pt(IV)-coordinated nitriles, Inorganica Chimica Acta, 2008, 361 (6) , pp. 1738-1743 (IF=1.846)ABSTRACT: The metal-mediated coupling between the nitriles RCN in the platinum(IV) complexes trans-[PtCl4(RCN)2] (RMe, Et, CH2Ph, Ph), cis/trans-[PtCl4(MeCN)(Me2SO)] and the newly synthesized bifunctional oximehydroxamic acid, viz. N,2-dihydroxy-5-(1-hydroxyiminoethyl)benzamide, proceeds

smoothly in CH2Cl2 at 40–45 °C to accomplish the new metallaligands HNC(R)ONHC(O)C6H3(2-OH)(5-C(Me)NOH) with pendant oxime functionalities due to the regioselective addition of the reagent via its hydroxamic groups. The obtained iminoligands exist in hydroxamic/hydroximic tautomeric equilibrium in solution. The structures of the isolated compounds are based on elemental analyses (C, H, N), IR, 1D 1H, 13C{1H}, and 2D NMR correlation experiments, i.e. 1H,13C-COSY, 1H,13C long range COSY, 1H,15N-COSY, and 1H,15N long range COSY.11. Garnovskii, A.D., Vasilchenko, I.S., Garnovskii, D.A., Kharisov, B.I. Molecular design of mononuclear complexes of acyclic Schiff-base ligands, Journal of Coordination Chemistry, 2009, 62 (2), pp. 151-204 (IF=1.547)ABSTRACT: Data on molecular design of various types of mononuclear complexes of Schiff bases are generalized. Factors for variation of fine structure of Schiff-base ligand systems (metallocycle sizes and their number, nature of donor centers, aldehyde and amine fragments, co-ligands) are examined. A systematization of Salen complexes is offered. Electronic configurations of p- and d-metals in the coordination and organometallic compounds are taken into account in a series of chelate structures. Non-standard structures are emphasized, including various ligand chelates and molecular complexes.

Nikolay VOLOSHIN (h=7) 1. Voloshina, E.N., Wang, Y., Voloshin, N.A., Raabe, G., Gais, H.-J., Fleischhauer, J. 6-Methoxy-3,3′,3′-trimethylspiro[2H-1-benzopyran-2,1′ [2]oxaindan]: Separation of Enantiomers, Circular Dichroism Measurements and Determination of the Absolute Configuration, Zeitschrift fur Naturforschung - Section A Journal of Physical Sciences, 2003, 58 (7-8) , pp. 443-450 (IF=1.117)2. Voloshin, N.A., Chernyshev, A.V., Metelitsa, A.V., Besugliy, S.O., Voloshina, E.N., Sadimenko, L.P., Minkin, V.I. Photochromic spiro[indoline-pyridobenzopyrans]: Fluorescent metal-ion sensors, Arkivoc, 2004 (11) , pp. 16-24 (IF=1.252)ABSTRACT: By coupling 5-bromo-(chloro)-7-formyl-8-hydroxyquinoline with 2-methylene-1,3,3-trimethylindoline, the 6'-halogeno-spiro[indoline-2,2'-[3,2-h]-pyrido[2H-1]benzopyrans] 3 have been prepared and their photochromic behaviors studied. The photoinduced merocyanine forms 4 of the spiropyrans form fluorescent complexes with divalent metal ions (Mg2+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+).3. Gaeva, E.B., Metelitsa, A.V., Voloshin, N.A., Pimienta, V., Miceau, J.-C. Solvation effect and aggregation of semipermanent spiro[indole- phenanthrolinoxazines] in CH 3CN / H 2O binary solvent, Arkivoc, 2005 (7) , pp. 18-26 (IF= 1.252)ABSTRACT: For three 5-alkyloxyspiro[indolephenanthrolinoxazines], the open form possesses a low- polarity semi-quinoidal structure. In acetonitrile-water binary solvent, the merocyanine is stabilized by a specific interaction with a water molecule. At high water content, the hydrated open form gives rise to H-aggregates.4. Lukyanov, B.S., Metelitsa, A.V., Voloshin, N.A., Alexeenko, Yu.S., Lukyanova, M.B., Vasilyuk, G.T., Maskevich, S.A., Mukhanov, E.L Solid state photochromism of spiropyrans, International Journal of Photoenergy, 2005, 7 (1) , pp. 17-22 (IF=1.769)ABSTRACT: A series of spiropyrans possessing photochromic properties in solid state were investigated. UV irradiation (λmax = 365 nm) of the thin vacuum deposited spiropyran films results in conversion of the colorless form to the photocolored one. The reaction is photochemically and thermally reversible. The photochromic activity of the solid material and polystyrene matrix has been compared. Raman spectroscopy has been used for studying the influence of metallic surface on the adsorbed spiropyran layers.5. Glebov, E.M., Vorobyev, D.Yu., Grivin, V.P., Plyusnin, V.F., Metelitsa, A.V., Voloshin, N.A., Minkin, V.I., Micheau, J.C. Photochemistry of phenanthroline-containing spirooxazines in a low-temperature methanol matrix, Chemical Physics, 2006, 323 (2-3), pp. 490-500 (IF= 1.896)ABSTRACT: Both stationary and laser flash photolysis were applied to study the photochemistry of a closed A-form of phenanthroline-containing spirooxazines in a methanol matrix (77 K). One of spirooxazines was nonsubstituted (SPO1) and the second one (SPO2) had a long alkyl substituent, n-

C16H33, in the indoline part of the molecule. For SPO1, excitation of the A-form causes absorption of the B-form (600 nm) during the action of a laser pulse. Kinetics of a further increase in the concentration of B-form is determined by the inhomogeneity of a rigid matrix and is described by a set of exponents with characteristic times from hundreds of nanoseconds to tens of milliseconds. Absorption of the B-form is accompanied by absorption in the region of 400–750 nm, which belongs to X-isomer (an intermediate form of spirooxazine). The disappearance of X-isomer was described by a set of exponential functions with the characteristic times similar to those typical of the B-form appearance. For SPO1, only the B-form is accumulated during the stationary photolysis (X-isomer is completely transformed into the B-form). For SPO2, a range of characteristic times moves toward long times so that the X-isomer absorption is observed even upon stationary photolysis. Thus, a long X-isomer lifetime indicates that the B-form originates from the ground state of this intermediate. The existence of a long substituent substantially increases the time of X → B transformation in a frozen matrix. The appearance of a narrow absorption band at 600 nm immediately after the laser pulse was assigned to the formation of only one of the possible isomers of B-form upon X → B transformation.

6. Aldoshin, S.M., Sanina, N.A., Minkin, V.I., Voloshin, N.A., Ikorskii, V.N., Ovcharenko, V.I., Smirnov, V.A., Nagaeva, N.K. Molecular photochromic ferromagnetic based on the layered polymeric tris-oxalate of Cr(III), Mn(II) and 1-[(1′,3′,3′-trimethyl-6-nitrospiro[2H-1-benzopyran-2, 2′-indoline]-8-yl)methyl]pyridinium, Journal of Molecular Structure, 2007, 826 (2-3) , pp. 69-74 (IF=1.634)ABSTRACT: Basing on 1-[(1′,3′,3′-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2′-indoline]-8-yl)methyl] pyridinium chloride, a new bifunctional compound C31H26N3O16CrMn has been synthesized, which exhibits ferromagnetic (Tk = 5.1 K) and photochromic properties in the solid state.7. Nikolaeva, M.I., Korolev, V.V., Pritchina, E.A., Glebov, E.M., Plyusnin, V.F., Metelitsa, A.V., Voloshin, N.A., Minkin, V.I. Photochemistry of a 6′-cyanosubstituted spironaphthooxazine: Photo-induced decay of an open form, Journal of Physical Organic Chemistry, 2011, 24 (9) , pp. 833-842 (IF= 1.963)ABSTRACT: Photochemistry of three 6′-cyanosubstituted spironaphthooxazines (SNO) in ethanol matrices at 77 K was studied by means of ultraviolet (UV) and erythrocyte sedimentation rate (ESR) spectroscopy and quantum chemistry. The quantum yield of the open form photolysis is found to be 0.01–0.02, which is high enough for 77 K. For one of the SNO, the formation of a merocyanine form radical was observed. The radicals were formed by an H atom abstraction from the solvent molecule to the light-excited merocyanine isomers. The formation of a merocyanine radical represents a new specific channel of photochemically induced degradation of spirooxazines. Copyright © 2011 John Wiley & Sons, Ltd.

Victor KOGAN (h=18) 1. Tupolova, Yu.P., Kogan, V.A., Lukov, V.V., Popov, L.D., Gevorkyan, I.E., Vlasenko, V.G. Synthesis and magnetic properties of the novel binuclear copper(II) metallochelates with unsymmetrical exchange fragment including heterocyclic derivatives, Transition Metal Chemistry, 2007, 32 (5) , pp. 656-661 (IF=1.022)ABSTRACT: The series of the novel copper(II) binuclear metallochelates with unsymmetrical exchange fragment including pyrazolate bridge has been synthesized for the first time. The composition and structure of the prepared compounds have been established with the data of UR, NMR-H1, EXAFS spectroscopy as well as magnetochemical studies. The analysis of the influence of pyrazolate ion on the magnetic exchange interaction between two copper atoms has been carried out.2. Popov, L.D., Shcherbakov, I.N., Levchenkov, S.I., Tupolova, Y.P., Kogan, V.A., Lukov, V.V. Binuclear copper(II) and oxovanadium(IV) complexes with 2,6-diformyl-4-tert-butylphenol-bis-(1′-phthalazinylhydrazone). Synthesis, properties and quantum chemical study, Journal of Coordination Chemistry, 2008, 61 (3) , pp. 392-409 (IF=1.547)ABSTRACT: Four binuclear transition metal complexes: [Cu2L(μ-OCH3)] · CH3OH, [Cu2H2L(μ-Cl)Cl2] · (CH3OH), [Cu2H2L(μ-Br)Br2] · (CH3OH), [(VO)2H2L(μ-Cl)]Cl2 · (CH3OH) were synthesized by reaction of the Robson-type binucleating ligand H3L (2,6-diformyl-4-tert-butylphenol-bis-(1′-phthalazinylhydrazone)) with Cu(II) acetate, CuCl2, CuBr2 and VOCl2, correspondingly. IR and ESR spectra, elemental analysis, conductivity measurements, magnetochemical study and DFT calculations

were used to characterize the ligand and isolated complexes. The ligand is a NNONN donor and its degree of deprotonation varies with the metal salt used for reaction (triply deprotonated form L−3 is observed in reaction with copper(II) acetate, while monodeprotonated form H2L− is found in complexes obtained from metal halides). All complexes contain an endogenous phenoxide bridge and an exogenous methoxide, chloride or bromide bridge. Magnetic data reveal existence of antiferromagnetic interactions between the metal ions (experimental 2J values are −700, −73, −50 and −190 cm−1, correspondingly). Broken symmetry approach at the UB3LYP/6-31G(d) level was used to theoretically calculate spin-spin coupling between metal centers. Obtained values −570, −62, −53 and −214 cm−1 are rather close to experimental ones and reproduce their counterrelation. Spin density distribution in the singlet and triplet states of the complexes is discussed.3. Bulanov, A.O., Popov, L.D., Shcherbakov, I.N., Kogan, V.A., Barachevsky, V.A., Lukov, V.V., Borisenko, S.N., Tkachenko, Yu.N. Synthesis, IR, UV/vis-, 1H NMR and DFT study of chelatophore functionalized 1,3-benzoxazinone spiropyrans, Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy, 2008, 71 (3) , pp. 1146-1152 (IF=1.012)ABSTRACT: Six novel functionalized spiropyran's derivatives of 2H-1,3-benzoxazinone series were synthesized by introducing the substituents with chelating ability into 2H-chromene part of the 8′-formyl-7′-hydroxy-3-methyl-4-oxo-3,4-dihydro-2H-1,3-benzoxazine-2-spiro-2′-[2H]-chromene (I) by condensation with 2-aminophenol, 2-amino-4-methylphenol, 2-amino-4-nitrophenol, 2-amino-1-methylbenzimidazole, 4-amino-4H-1,2,4-triazole, N-(4-aminophenyl)acetamide. 1H NMR, UV/vis, IR spectroscopy combined with quantum-chemical calculations employing density functional theory (DFT) were used to study their structure. All substances, except 2-amino-4-nitrophenol derivative exist in solid state and in solution solely in closed spiroform, while the mentioned one undergoes partial spiropyran ring opening. In DMSO solution NMR spectra show ratio of 2:1 of closed and opened form, correspondingly.4. Tupolova, Y.P., Popov, L.D., Lukov, V.V., Shcherbakov, I.N., Levchenkov, S.I., Kogan, V.A., Maevskiy, O.V., (...), Zubenko, A.A. Crystal structure and magnetic properties of copper(II) and nickel(II) blnuclear complexes with bisacylhydrazones based on 2,6-diformyl-4-methylphenol, Zeitschrift fur Anorganische und Allgemeine Chemie, 2009, 635 (3) , pp. 530-536 (IF=1.117)5. L.D. Popov, Yu.P. Tupolova, V.V. Lukov, I.N. Shcherbakov, A.S. Burlov, S.I. Levchenkov, V.A. Kogan, K.A. Lyssenko, E.V. Ivannikova, E.V. Physico-chemical study of first row transition metal ions coordination compounds with N,N′-bis(2-tosylaminobenzylidene)-1,3-diaminopropanol. The crystal structure of bis-azomethine and its cobalt(II) complex, Inorganica Chimica Acta, 2009, 362 (6) , pp. 1673-1680 (IF=1.846)ABSTRACT: The novel Cu(II), Ni(II), Zn(II), Co(II) coordination compounds with Schiff base ligand – N,N′-bis(2-tosylaminobenzylidene)-1,3-diaminopropanol have been synthesized and studied. The structures of bis-azomethine as well as Co(II) and Zn(II) mononuclear metallochelates have been determined by X-ray analysis. The magnetic properties of all complexes were studied and interpreted in terms of HDVV theory. It was shown that exchange interaction in binuclear copper(II) complexes was affected by tosyl groups.6. Popov, L.D., Morozov, A.N., Shcherbakov, I.N., Tupolova, Y.P., Lukov, V.V., Kogan, V.A. Metal complexes with polyfunctional ligands based of bis(hydrazones) of dicarbonyl compounds, Russian Chemical Reviews, 2009, 78 (7) , pp. 643-658 (IF=2.644)ABSTRACT: Data on the metal complexes with bis(hydrazones) obtained from various classes of dicarbonyl compounds are generalized and described systematically. The structure and complexing properties of bis(hydrazones) are considered and the factors influencing structures of the metal complexes are analyzed. The relationships between the structures and physicochemical properties of the considered compounds are discussed.7. Mishchenko, A.V., Lukov, V.V., Popov, L.D., Tupolova, Yu.P., Shcherbakov, I.N., Levchenkov, S.I., Kogan, V.A., (...), Askalepova, O.I. Synthesis and physico-chemical study of complexation of glyoxylic acid aroylhydrazones with Cu(II) in solution and solid phase, Journal of Coordination Chemistry, 2011, 64 (11) , pp. 1963-1976 (IF= 1.547)ABSTRACT: A series of copper(II) binuclear metallochelates with glyoxylic acid aroylhydrazones have been synthesized. The composition and structure were established with infrared, UV-Vis, 1H NMR,

extended X-ray adsorption fine structure spectroscopy as well as magnetochemical studies and potentiometry. The proton-donor and proton-acceptor features of the ligand systems play a key role in the formation of the complexes.8. Popov, L.D., Levchenkov, S.I., Shcherbakov, I.N., Lukov, V.V., Suponitsky, K.Y., Kogan, V.A. Binuclear copper(II) complexes of Schiff base ligand derived from 1-phenyl-3-methyl-4-formylpyrazol-5-one and 1,3-diaminopropan-2-ol: Synthesis, structure and magnetic properties, Inorganic Chemistry Communications, 2012, 17 , pp. 1-4 (IF=1.972) ABSTRACT: Two novel binuclear heterobridged copper(II) Schiff base complexes of general formula [Cu2L(Pz)] (1) and [Cu2L(Az)(DMSO)]·DMSO (2) (where L = trianion of bis-azomethine derived from 1-phenyl-3-methyl-4-formylpyrazol-5-one and 1,3-diaminopropan-2-ol, Az = anion of 7-azaindole, Pz = pyrazolate anion) were synthesized and studied by IR spectroscopy and X-ray crystallography. Temperature dependence of magnetic susceptibility measurements show an antiferromagnetic coupling between two copper(II) ions in complex 1 (2 J = − 449) and ferromagnetic coupling in complex 2 (2 J = 106 cm− 1).

Igor VASILCHENKO (h=12)1. Skopenko, V.V., Amirkhanov, V.M., Sliva, T.Yu., Vasilchenko, I.S., Anpilova, E.L., Garnovskii, A.D. Various types of metal complexes based on chelating β-diketones and their structural analogues, Russian Chemical Reviews, 2004, 73 (8) , pp. 737-752 (IF=2.644)ABSTRACT: Data on the synthesis and structures of β-diketonates and their N,P-containing structural analogues are generalised and described systematically. The possibility of creating diverse metal complexes with various modes of coordination of typical chelating ligands is discussed. The bibliography includes 200 references.2. Alexeev, Yu.E., Vasilchenko, I.S., Kharisov, B.I., Blanco, L.M., Garnovskii, A.D., Zhdanov, Yu.A. Review: Synthetically modified carbohydrates as ligands Journal of Coordination Chemistry, 2004, 57 (17-18), pp. 1447-1517 (IF=1.547)ABSTRACT: The coordinative properties of synthetically modified carbohydrates to metal cations are reviewed. Such metal complexes are distinct, owing to the structural diversity of the ligands and coordination modes. The influences of complex-formation conditions on chemical properties of modified carbohydrates, as well as on organic reactions (especially diastereoselective ones), are examined. In addition, this manuscript demonstrates the practical importance of the coordination interactions.3. Vasilchenko, I.S., Kuz'Menko, T.A., Shestakova, T.E., Borisenko, R.N., Divaeva, L.N., Burlov, A.S., Borisenko, N.I., (...), Garnovskii, A.D. Novel N-benzimidazolyl-2-thione o-tosylamino(hydroxy)azomethinic tautomeric ligand systems and their metallochelates, Arkivoc, 2005 (7) , pp. 82-90 (IF=1.252)ABSTRACT: Novel ligand systems –azomethinic derivatives of 1-amino-3-methyl-1,3-dihydrobenzoimidazole-2-thione and o-tosylamino(hydroxy)benzaldehydes – are synthesized as a result of a multistage procedure and are evaluated. Study of the coordination activity of these compounds has shown that they form complexes ML2 with transition d-elements containing MN4S2 and MN2O2S2 coordination units in solid and in solution. Electrospray mass-spectrometryresults show the possibility of formation of M2L2 and M2L3 complexes in the vapor phase.4. Morkovnik, A.S., Divaeva, L.N., Nelyubina, Y.V., Lyssenko, K.A., Vasilchenko, I.S. Structure and tautomerism of 2-benzimidazolylthioureas, Mendeleev Communications, 2007, 17 (4), pp. 224-226 (IF=0.901)ABSTRACT: The results of quantum-chemical, 1H NMR and X-ray studies demonstrated that N-2-benzimidazolylthioureas exist in 1,3-dihydrobenzimidazolinylidenetautomeric forms.5. Garnovskii, A.D., Vasilchenko, I.S., Garnovskii, D.A., Kharisov, B.I. Molecular design of mononuclear complexes of acyclic Schiff-base ligands Journal of Coordination Chemistry, 2009, 62 (2) , pp. 151-204 (IF=1.547) ABSTRACT: Data on molecular design of various types of mononuclear complexes of Schiff bases are generalized. Factors for variation of fine structure of Schiff-base ligand systems (metallocycle sizes and

their number, nature of donor centers, aldehyde and amine fragments, co-ligands) are examined. A systematization of Salen complexes is offered. Electronic configurations of p- and d-metals in the coordination and organometallic compounds are taken into account in a series of chelate structures. Non-standard structures are emphasized, including various ligand chelates and molecular complexes.6. Garnovskii, A.D., Sadimenko, A.P., Vasilchenko, I.S., Garnovskii, D.A., Sennikova, E.V., Minkin, V.I. Chapter 5 Hetarylazomethine Metal Complexes, Advances in Heterocyclic Chemistry, 2009, 97 , pp. 291-392 (IF=1.818)

Ali URAEV (h=9) 1. Uraev, A.I., Vlasenko, V.G., Kharisov, B.I., Blanco, L.M., Shuvaev, A.T., Vasilchenko, I.S., Garnovskii, A.D., Elizondo, N.V. Synthesis and EXAFS investigation of azomethynic copper metallochelates with an N,S,O ligand environment, Polyhedron, 2000, 19 (22-23) , pp. 2361-2366 (IF=2.057)ABSTRACT: Neutral copper complexes of different composition (CuL2 1 and CuL2OAc) and structure were obtained by coupling the 1-phenyl(isopropyl)-3-methyl-4-(N-substituted)aldimino-5-oxy(thio, seleno)pyrazoles (HL1), and 2-hydroxy(tosylamino)-N-(8-quinolyl)benzaldimine (HL2) with copper(II) acetate. According to X-ray structural data, the CuL2 1 complexes possess the pseudotetrahedral structure, and the CuL2OAc complexes, the square-pyramidal one. The complexes were studied by EXAFS spectroscopy. EXAFS spectral data on the nearest ligand environment show a good correlation with the X-ray structural results.2. Garnovskii, A.D., Uraev, A.I., Minkin, V.I. Metal complexes from aryl and hetarylazocompounds, Arkivoc, 2004 (3) , pp. 29-41 (IF=1.252)ABSTRACT: Significance of the phase transfer catalysis for the synthesis of less accessible aromatic and heterocyclic compounds is emphasized. A series of novel azo compounds containing pyrazole and quinoline fragments has been prepared and employed in the synthesis of 3d-metal coordination compounds with desired types of the coordination site.3. Ali I. Uraev, Igor S. Vasilchenko, Vladimir N. Ikorskii, Tatyana A. Shestakova, Anatolii S. Burlov, Konstantin A. Lyssenko, Valery G. Vlasenko, Tatyana A. Kuz’menko, Ludmila N. Divaeva, Irina V. Pirog, Gennadii S. Borodkin, Igor E. Uflyand, Mikhail Yu. Antipin, Victor I. Ovcharenko, Alexander D. Garnovskii, Vladimir I. Minkin Copper(II) dimers with ferromagnetic intra- and intermolecular exchange interactions, Mendeleev Communications, 2005, (4), pp. 133-135 (IF=0.901)ABSTRACT: Dimers based on CuII azomethine complexes exhibited both intra- and intermolecular ferromagnetic exchange interactions, as found from magneto-structural correlations.4. Vlasenko, V.G., Uraev, A.I., Garnovskii, A.D. XAFS study of Cu(II), Ni(II) and Co(II) β-aminovinylketone complexes, Physica Scripta, 2005, V.115 , pp. 362-364 (IF=1.204)ABSTRACT: A series of mononuclear complexes with 1-phenyl-3-(2-phenylsulfanyl-phenylamino)-pent-2-en-1-one (Ia) and 1-phenyl-3-(2-phenylsulfanyl-phenylamino)-but-2-en-1-one (Ib) ligands, which mimics the active site of copper, cobalt and nickel proteins, have been synthesized and structurally characterized by EXAFS.EXAFS analysis has shown that NiL2 and CoL2 complexes with L = Ia are hexacoordinated by added Ni-S and Co-S bonds in contrast with square-planar NiL2 (CoL2) complexes with L = Ib. The CuL2 complexes with both L = Ia and L = Ib ligands have the CuN2O2 planar coordination.5. A.D. Garnovskii, V. N. Ikorskii, A.I. Uraev, I.S. Vasilchenko, A.S. Burlov, D.A. Garnovskii, K.A. Lyssenko, V.G. Vlasenko, T.E. Shestakova, Y.V. Koshchienko, T.A. Kuz’menko, L.N. Divaeva, M.P. Bubnov, V.P. Rybalkin, O.Yu. Korshunov, I.V. Pirog, G.S. Borodkin, V.A. Bren, I.E. Uflyand, M.Yu. Antipin & V.I. Minkin The novel azomethine ligands for binuclear copper(II) complexes with ferro- and antiferromagnetic properties, Journal of Coordination Chemistry, 2007, 60 (14) , pp. 1493-1511 (IF=1.547)ABSTRACT: A series of novel binuclear ferro- and antiferromagnetic Cu(2+) chelates of structurally broadly varied Schiff bases (derived from o-tosylamino(hydroxyl)benzaldehydes and monoalkylated o-phenylenediamine, o-aminophenol, o-aminothiophenol, 1,2-diaminobenzimidazole, 1-aminobenzimidazoline-2-thione) and β-diketimines (derived from 2,6-di-i-Pr-aniline) has been prepared. The tautomerism of the ligands and structureof their copper complexes have been studied with the use of

IR, 1H NMR EPR and EXAFS spectroscopy. Molecular and crystal structure of a β-diketimine copper dimer has been determined by X-ray crystallography. The magnetic measurements (2–300 K) performed for all the complexes showed that the ferro- and antiferromagnetic character of the exchange interaction depends both on the structure of the coordination site (origin of the ligating centers) and the structure of the ligands (in particular, on the type of the cycle annelated to the bridging fragment). Whereas S-binding metal chelates 13 (X = NTs, Y = S, R = H) are diamagnetic, the complexes 15 with annelated azole moieties are ferromagnetic.

Anatoliy UZDENSKY 1. Uzdensky, A.B., Savransky, V.V.Single neuron response to pulse-periodic laser microirradiation: Action spectra and two-photon effect // Journal of Photochemistry and Photobiology B: Biology 1997 39 (3) , pp. 224-228 Цит12 (IF=2,814)ABSTRACT: Cytoplasm regions of crayfish stretch receptor neurons were irradiated by the microbeam of a pulse-periodic dye laser (diameter 5 μm, pulse duration 15 nsec, pulse frequency 400 Hz). Irradiation wavelengths varied from 434 to 600 nm, and beam intensity (at 441.6 nm) from 0.25 to 5 X 103 W cm-2 (mean), or from 0.4 to 8 X 108 W cm-2 (peak). Under irradiation neuron firing typically accelerated and then inhibited. In some cases it accelerated again and then abruptly and irreversibly ceased. Action spectra of parameters describing different response phases had the flavin-like maximum at 460 nm. This suggests flavins as a primary intracellular photoreceptor for blue laser light. It was also found that firing acceleration rate quadratically depended on peak beam intensity. This finding indicates the participation of two photon processes in neuronal membrane alteration leading to firing acceleration. Parameters describing inhibition phase depended on beam intensity linearly. That is characteristic for usual single-photon process. 2. Uzdensky, A.B., Mironov, A.F. Photodynamic inactivation of the single crayfish nerve cell: Dynamics of electrophysiological responses and comparison of photosensitisers //Lasers in Medical Science 1999 14 (3), pp. 185-195 Цит19 (IF=2,004)ABSTRACT: The study of single neuron response to photodynamic effect provides a means for the study of the dynamics of cytotoxic events leading to cell death and allows comparison of the phototoxicity of different photosensitisers, Isolated crayfish stretch receptor neurons were photosensitised for 30 min, then irradiated with a He-Ne laser (632.8 nm; 0.3 W/cm2) until irreversible firing cessation. The dynamics of neuron firing frequency were continuously recorded throughout. The following photosensitisers were studied: methylene blue, janus green B, protoporphyrin IX, chlorins e6 and p6, haematoporphyrin derivative (Photoheme) and sulphonated aluminium phthalocyanine (Photosens). Nerve cells were found to be insensitive to either He-Ne laser irradiation or photosensitisation alone, but very vulnerable to the photodynamic effect: neurons changed firing rate and died at nanomolar concentrations of photosensitisers. The dynamics of neuron responses was found to depend on photosensitiser type and concentration. The current approach provides a means of evaluation of initial threshold cell membrane alteration and cytotoxic events leading to cell death. The dependence of firing acceleration rate and neuron lifetime on photosensitiser concentration additionally allowed comparison of efficiencies of different photosensitisers. Photosens, Photoheme and chlorin p6 were found to be the most potent photosensitisers: neurons responded to their photodynamic effects at concentrations as low as 1-5 nM. 3. Uzdensky, A.B., Zhavoronkova, A.A., Dergacheva, O.Y.Firing inhibition processes in the response dynamics of isolated crayfish nerve cell to the photodynamic effect of sulphonated aluminium phthalocyanine: Participation of free radicals and Ca2+ // Lasers in Medical Science 2000 15 (2) , pp. 123-130 Цит. 20 (IF=2,004)ABSTRACT: Chemical modifications allows the enhancement or attenuation of the cell response to photodynamic effect and provides information on the mechanisms of this effect. Isolated crayfish neurons were incubated for 30 min with 10-7 M Photosens (AlPcS(n)) and irradiated by He-Ne laser (632.8 nm, 0.3 W/cm2). Such treatment caused firing inhibition until it was irreversibly abolished. The antioxidants homocarnosine, DABCO or ascorbate, pro-oxidant, FeSO4 or a mixture of FeSO4 and ascorbate; Ca2+ modulators, CdCl2, verapamil, EDTA, dantrolene, caffeine, theophylline, or a threefold CaCl2 concentration were used to modify neuron response (firing inhibition and abolition). Homocarnosine,

CdCl2, DABCO, dantrolene, and caffeine or theophylline added 30-90 min before irradiation, increased neuron lifetime under the photodynamic effect of Photosens whereas FeSO4/ascorbate, EDTA, threefold Ca2+ concentration or caffeine (added 5 min before irradiation) decreased neuron lifetime. It is concluded that, free radical processes and Ca2+ participate in the Photosens-induced photodynamic inhibition and subsequent irreversible abolition of neuron firing. 4. Uzdensky, A.B., Dergacheva, O.Yu., Zhavoronkova, A.A., Ivanov, A.V., Reshetnikov, A.V., Ponomarev, G.V.Photodynamic effect of deuteroporphyrin IX and hematoporphyrin derivatives on single neuron // Biochemical and Biophysical Research Communications 2001 281 (5) , pp. 1194-1199 Цит9 (IF=2,484)ABSTRACT: The photodynamic effects of 6 new deuteroporphyrin IX derivatives with different amphiphilicity and lipophilicity, as well as effects of known hematoporphyrin derivatives Photofrin II and Photoheme on isolated crayfish mechanoreceptor neurons were studied. After 30 min photosensitization, neurons were irradiated with He-Ne laser (632.8 nm, 0.3 W/cm 2), and changes in their firing frequency were recorded. Neuron firing was shown to be very sensitive to photodynamic effect of the studied deuteroporphyrin IX derivatives causing irreversible firing abolition at pikomolar concentrations while Photoheme and Photofrin II were effective in the nanomolar range. The most effective sensitizers were 4-(1-methyl-3-hydroxybutyl)-and 4-(1-methyl-2-acetyl-3-oxobutyl)-deuteroporphyrins. Extinction and amphiphilicity were shown to be the most important properties determining photodynamic efficiency of the studied photosensitizers. 5. Uzdensky, A.B., Ma, L.-W., Iani, V., Hjortland, G.O., Steen, H.B., Moan, J.Intracellular localisation of hypericin in human glioblastoma and carcinoma cell lines // Lasers in Medical Science 2001 16 (4) , pp. 276-283 Цит. 45 (IF=2,004)ABSTRACT: Hypericin, a natural polycyclic quinone extracted from Hypericum perforatum, has been recently shown to be a powerful sensitiser for photodynamic therapy (PDT). However, its intracellular localisation remains unclear and contradictory. In the present work we compared the intracellular localisation of hypericin in three cultured cell lines (adenocarcinoma cells WiDr, carcinoma cells NHIK 3025 and glioblastoma cells D54Mg) with the distribution of fluorescent probes specific to lysosomes (LysoTracker Blue DND-22), mitochondria (MitoTracker Green FM) and endoplasmic reticulum (ERTracker Blue-White DPX). It was shown that the hypericin staining pattern was different compared to the intracellular distribution of mitochondria or lysosomes. Hypericin was concentrated in the perinucleolar cytoplasmic area mainly on one side of the nucleus - the region rich in endoplasmic reticulum and Golgi. Sometimes nuclear envelope was also stained. Plasma membrane was not stained but the dye was often accumulated in the intercellular space between the tightly contacting WiDr cells in colonies. Hypericin concentrations of 10 μM or less were not toxic for WiDr cells in the dark. Orange light (λ max ≈600 nm; 6 mW/cm 2) killed the cells stained with 1 μM hypericin with LD 50 ∼ 1J/cm 2. 6. Uzdensky, A.B., Iani, V., Ma, L.-W., Moan, J.Photobleaching of hypericin bound to human serum albumin, cultured adenocarcinoma cells and nude mice skin // Photochemistry and Photobiology 2002 76 (3) , pp. 320-328 Цит20 (IF=2,413)ABSTRACT: Hypericin is a promising photosensitizer for photodynamic therapy (PDT) characterized by a high yield of singlet oxygen. Photobleaching of hypericin has been studied by means of absorption and fluorescence spectroscopy in different biological systems: in human serum albumin solution, in cultured human adenocarcinoma WiDr cells and in the skin of nude mice. Prolonged exposure to light (up to 95 min, 100 mW/cm 2) of wavelength around 596 nm induced fluence-dependent photobleaching of hypericin in all studied systems. The photobleaching was not oxygen dependent, and singlet oxygen probably played no significant role. Emission bands in the spectral regions 420-560 nm and above 600 nm characterize the photoproducts formed. An emission band at 615-635 nm was observed after irradiation of cells incubated with hypericin or of mouse skin in vivo but not in albumin solution. The excitation spectrum of these products resembled that of hypericin. Hypericin appears to be more photostable than most sensitizers used in PDT, including mTHPC and Photofrin. 7. Uzdensky, A., Bragin, D., Kolosov, M., Dergacheva, O., Fedorenko, G., Zhavoronkova, A.Photodynamic inactivation of isolated crayfish mechanoreceptor neuron: Different death modes under

different photosensitizer concentrations // Photochemistry and Photobiology 2002 76 (4) , pp. 431-437 Цит24 (IF=2,413)ABSTRACT: To study the mechanism of photodynamic nerve cell killing, isolated crayfish mechanoreceptor neurons were photosensitized by the sulfonated aluminum ophthalocyanine Photosens. Neuron activity was continuously recorded until irreversible abolition. Intense (10 -5 M Photosens) or weak (10 -7 M Photosens) photosensitization induced different bioelectric neuron responses: firing activation followed by irreversible depolarization block or gradual inhibition until firing abolition, respectively. These bioelectric responses were accompanied by different biochemical and morphological changes. In the case of intense photosensitization, neuron nuclei swelled and then shrank. Succinate dehydrogenase (SDH) was inhibited, and the plasma membrane was compromised just after firing cessation. Weak photosensitization did not induce these changes but caused swelling of the endoplasmic reticulum and destruction of the matrix, cristae and membranes in some of the mitochondria. Other mitochondria, however, retained the normal structure. Plasma membrane damage, SDH inhibition, nucleus shrinkage and impairment of the nuclear border occurred after 2-4 h. It is concluded that intense PDT induced necrotic processes during irradiation, whereas weaker impact caused delayed necrosis 2-4 h later. The observed electrophysiological neuron responses to photodynamic therapy may be considered as early hallmarks of different modes of forthcoming cell death.8. Uzdensky, A.B., Bragin, D.E., Kolosov, M.S., Kubin, A., Loew, H.G., Moan, J.Photodynamic effect of hypericin and a water-soluble derivative on isolated crayfish neuron and surrounding glial cells // Journal of Photochemistry and Photobiology B: Biology 2003 72 (1-3) , pp. 27-33 Цит17 (IF=2,814)ABSTRACT: Hypericin (Hyp) has been proposed as a fluorochrome for fluorescence diagnostics and as a photosensitizer for photodynamic therapy of cancer. However, its insolubility in water is a serious drawback. A novel water-soluble hypericin derivative (Hyp-S) has been constructed, using polyvinylpyrrolidone as a carrier. We used the crayfish stretch receptor, consisting of receptor neuron and satellite glial cells, for comparison of the photodynamic effects of Hyp and Hyp-S. Hyp-S was more toxic in the dark than Hyp and inactivated the neurons at concentrations exceeding 4 μM while Hyp was toxic to the neurons only at the concentrations larger than 20 μM. Electrophysiological investigations revealed polyphasic neuron responses to photosensitization with Hyp as well as with Hyp-S (1 μM concentration, 30 min incubation; irradiation with filtered light from a lamp with an emission maximum near 600 nm and an intensity of 0.2 W/cm2). In the concentration range 1-4 μM Hyp-S was more phototoxic than Hyp. Fluorescence microscopy showed that both sensitizers were predominately localized in the glial envelope surrounding the neuron. A minor fraction of hypericin was found in the neuron perinuclear area rich in cytoplasm organelles. This suggests the potential application of Hyp and Hyp-S for visualization and selective photodynamic treatment of malignant gliomas. 9. Uzdensky, A., Juzeniene, A., Ma, L.-W., Moan, J.Photodynamic inhibition of enzymatic detachment of human cancer cells from a substratum // Biochimica et Biophysica Acta - General Subjects 20041670 (1), pp. 1-11 Цит19 (IF=5,0)ABSTRACT: Photodynamic therapy (PDT) is currently used for cancer treatment. It is shown that sublethal PDT of human WiDr adenocarcinoma cells and D54Mg glioblastoma cells with 5-aminolevulinic acid (ALA), disulfonated tetraphenylporphyrine (TPPS 2a), or MitoTracker Red (MTR) inhibits their trypsin-induced detachment from a plastic substratum. TPPS 2a was bound selectively to the plasma membrane, whereas MTR was found in mitochondria. Both granular and diffuse fluorescence of ALA-derived protoporphyrin IX (PpIX) was observed in the perinuclear cytoplasm but not in the plasma membrane of WiDr cells stained for 2 h with 1 mM ALA. In D54Mg cells, PpIX fluorescence was observed not only in the cytoplasm but also in the plasma membrane. Fluorescence measurements showed a progressive accumulation of PpIX in the WiDr cells during incubation with ALA and a PpIX efflux into the medium after 1 h or longer incubation. PpIX retained in the plasma membrane during efflux may be responsible for PDT-induced impairment of cell adhesion. On the other hand, MTR-PDT or ALA-PDT after 15-min incubation, when the newly synthesized PpIX should remain in mitochondria, also inhibited enzymatic cell detachment. Therefore, photodynamic targeting of mitochondria, remote from the cell

surface where adhesion occurs, may disturb cell adhesion. Photodynamic inhibition of enzymatic cell detachment may be related to PDT-induced inhibition of tumour metastasis.

10. Uzdensky, A.B., Dergacheva, O.Y., Zhavoronkova, A.A., Reshetnikov, A.V., Ponomarev, G.V.Photodynamic effect of novel chlorin e6 derivatives on a single nerve cell // Life Sciences 2004 74 (17), pp. 2185-2197 Цит21 (IF=2,527)ABSTRACT: Chlorin e6 and its derivatives are promising sensitizers for photodynamic therapy (PDT). In order to compare the photodynamic effects of 8 novel derivatives of chlorin e6 and to explore some mechanisms of their effects at the cellular level, we studied PDT-induced changes in bioelectric activity of crayfish mechanoreceptor neuron that was used as a sensitive experimental model. Neurons were insensitive to red laser irradiation (632.8 nm; 0.3 W/cm2) or to photosensitizers alone, but changed firing rate and died under the photodynamic effect of nanomolar concentrations of sensitizers. The dynamics of neuron responses depended on photosensitizer type and concentration. The dependence of neuron lifetime on photosensitizer concentration allowed comparing efficiencies of different photosensitizers. Radachlorin was the most potent photosensitizer comparable with mTHPC. High photodynamic efficiency of some chlorin e6 derivatives was related to weak dependence of neuron lifetime on sensitizer concentration, indicating to the initiation of 2-3 secondary processes such as free radical membrane damage by one absorbed photon. Photodynamic efficiency of sensitizers depended on amphiphilicity influencing their intracellular localization. 11. Uzdensky, A.B., Juzeniene, A., Kolpakova, E., Hjortland, G.-O., Juzenas, P., Moan, J.Photosensitization with protoporphyrin IX inhibits attachment of cancer cells to a substratumBiochemical and Biophysical Research Communications 2004 322 (2), pp. 452-457 Цит22 (IF=2,484)ABSTRACT: Effects of photodynamic therapy (PDT) on adhesion of human adenocarcinoma cells of the line WiDr to a plastic substratum were investigated. Protoporphyrin IX induced by 5-aminolevulinic acid (ALA) was used as a photosensitizer. Light exposure inhibited attachment of suspended cells to a substratum. The adhesion was most strongly pronounced for light exposures around 200 mJ/cm 2 causing cell death. However, sub-lethal exposures (42 mJ/cm 2, 97% survival) inhibited cell adhesion as well. Sub-lethal ALA-PDT increased the intracellular space in dense colonies of WiDr cells. This was attributed to formation of lamellipodia between the cells and to increased numbers of focal contacts containing α Vβ 3 integrin in some of the cells. The E-cadherin distribution was not changed by the treatment. Complex processes, including changes in cellular shape and reorganization of the cytoskeleton, are suggested to participate in the observed ALA-PDT effect on the cell adhesion. 12. Uzdensky, A., Kolosov, M., Bragin, D., Dergacheva, O., Vanzha, O., Oparina, L.Involvement of adenylate cyclase and tyrosine kinase signaling pathways in response of crayfish stretch receptor neuron and satellite glia cell to photodynamic treatmentGLIA 2005 49 (3) , pp. 339-348 Цит20 (IF=4,82)ABSTRACT: Neuroglial interactions are most profound during development or damage of nerve tissue. We studied the responses of crayfish stretch receptor neurons (SRN) and satellite glial cells to photosensitization with sulfonated aluminum phthalocyanine Photosens. Although Photosens was localized mainly in the glial envelope, neurons were very sensitive to photodynamic treatment. Photosensitization gradually inhibited and then abolished neuron activity. Neuronal and glial nuclei shrank. Some neurons and glial cells lost the integrity of the plasma membrane and died through necrosis after the treatment. The nuclei of other glial cells but not neurons become fragmented, indicating apoptosis. The number of glial nuclei around neuron soma increased, probably indicating proliferation for enhanced neuron protection. Adenylate cyclase (AC) inhibition by MDL-12330A, or tyrosine kinase (TK) inhibition by genistein, shortened neuron lifetime, whereas AC activation by forskolin or protein tyrosine phosphatases (PTP) inhibition by sodium orthovanadate prolonged neuronal activity. Therefore, cAMP and phosphotyrosines produced by AC and TK, respectively, protected SRN against photoinactivation. AC inhibition reduced photodamage of the plasma membrane and subsequent necrosis in neuronal and glial cells. AC activation prevented apoptosis in photosensitized glial cells and stimulated glial proliferation. TK inhibition protected neurons but not glia against photoinduced membrane permeabilization and subsequent necrosis whereas PTP inhibition more strongly protected glial cells. Therefore, both signaling pathways involving cAMP and

phosphotyrosines might contribute to the maintenance of neuronal activity and the integrity of the neuronal and glial plasma membranes. Adenylate cyclase but not phosphotyrosine signaling pathways modulated glial apoptosis and proliferation under photooxidative stress.13. Uzdensky, A., Kolpakova, E., Juzeniene, A., Juzenas, P., Moan, J.The effect of sub-lethal ALA-PDT on the cytoskeleton and adhesion of cultured human cancer cells // Biochimica et Biophysica Acta - General Subjects 2005 1722 (1) , pp. 43-50 Цит23 (IF=5.0)ABSTRACT: 5-Aminolevulinic acid (ALA), a precursor of the endogenous photosensitizer protoporphyrin IX, is used in the photodynamic therapy (PDT) of cancer. Sub-lethal ALA-PDT (1-min irradiation with 370-450 nm blue light, 0.6 mW/cm 2 after 2-h incubation with 1 mM ALA) has been earlier shown to change cell morphology and to inhibit both trypsin-induced detachment of cultured cancer cells from the plastic substrata and cell attachment to the bottom of the plastic well plates. In the present study, we found that such treatment of human adenocarcinoma WiDr cells grown in dense colonies stimulated the formation of actin cortex between cells in the colonies and increased the number of actin stress fibres in some, but not in all, cells. However, ALA-PDT did not change the microtubular cytoskeleton in these cells. A similar treatment of glioblastoma D54Mg cells, which grow separately and communicate by protrusions, caused loss of fibrillar actin structures in growth cones, retraction of protrusions, and surface blebbing in some cells. The application of the cytoskeleton inhibitors cytochalasin D, colchicine or taxol showed that the inhibition of trypsin-induced detachment of photosensitized WiDr cells was related to ALA-PDT-induced changes in actin and microtubular cytoskeleton. Some signal transduction processes are suggested to be involved in ALA-PDT-induced changes in cytoskeleton, cell shape, and adhesion14. Kolosov, M., Uzdensky, A.Crayfish mechanoreceptor neuron prevents photoinduced apoptosis of satellite glial cells // Brain Research Bulletin 2006 69 (5), pp. 495-500 Цит14 (IF=2,818)ABSTRACT: Interactions between neurons and glia play a key role in the development, functioning and survival of the nervous system. However, the influence of neurons on glial cells has received less attention than the role of glia in supporting neural functions. We here investigated the role of isolated crayfish stretch receptor neuron in the death of satellite glial cells under photodynamic impact. After staining with aluminum phthalocyanine photosens, the neuronal cell body was locally irradiated with a focused beam of He-Ne (633 nm, 200 W/cm2) or semiconductor laser (650 nm, 50 W/cm2). This rapidly abolished neuronal activity. The whole preparation was then subjected to total laser irradiation with lower intensity (633 nm, 0.3 W/cm2), which induced death of glial cells. Double staining of the preparation with propidium iodide and Hoechst 33342 in the following 6-7 h allowed the visualization of necrotic, apoptotic and alive cells. Previous neuron inactivation with the focused laser beam was found to increase photodynamically-induced apoptosis but not necrosis of satellite glial cells enwrapping the axon. Therefore, the intact neuronal cell body protected satellite glial cells against photoinduced apoptosis. Altogether the data indicate that mechanoreceptor neurons release some signaling molecules involved in the prevention of glial apoptosis. This may provide integrity of the stretch receptor organ and its resistance to injurious factors. 15. Lobanov, A.V., Uzdensky, A.B.PDT-induced death of sensory neurons and glial cells in the isolated crayfish stretch receptor after proteolytic treatment //Journal of Neuroscience Research 2005 82 (6) , pp. 866-874 Цит4 (IF=2,738)ABSTRACT: To study the involvement of neuroglial interactions in photodynamic damage of crayfish stretch receptor, which consists of only two neurons surrounded by satellite glial cells (SGCs), we attempted to proteolytically uncouple neurons and glia and then compare the responses of these cells to photosensitization when intercellular communications were intact or impaired. After incubation of isolated stretch receptors with pronase or collagenase they were photosensitized with Photosens, a mixture of sulfonated alumophthalocyanines AIPcSn (n = 2, 3, and 4; mean n = 3.1). In the next 6 hr the preparations were double fluorochromed with propidium iodide and Hoechst-33342 to visualize necrotic and apoptotic cells. Proteolytic treatment shortened bioelectric neuron response and precipitated its functional inactivation; however, it did not significantly impair neuron morphology and did not induce its necrosis either in the darkness or under photosensitization. Photodynamic treatment induced necrosis of neurons and SGC and apoptosis of glial cells. Pronase but not collagenase increased percent of necrotic and apoptotic SGCs in the darkness and thus reduced the number of glial cells around the neuron; however, both pronase

and collagenase prevented photodynamically induced apoptosis of glial cells. The involvement of neuron-to-glia signaling interactions in this phenomenon is suggested.16. Uzdensky, A., Lobanov, A., Bibov, M., Petin, Y.Involvement of Ca2+ - and cyclic adenosine monophosphate- mediated signaling pathways in photodynamic injury of isolated crayfish neuron and satellite glial cells // Journal of Neuroscience Research 2007 85 (4), pp. 860-870 Цит16 (IF=2,738)ABSTRACT: To investigate the mechanisms of oxidative injury of neurons and glia, we studied the photodynamic effect on isolated stretch receptor that consists of only two sensory neurons enwrapped by satellite glial cells. Photodynamic therapy (PDT), a potent inducer of oxidative stress, is a prospective method for destruction of brain tumors. PDT induced functional inactivation and necrosis of neurons, necrosis, apoptosis, and proliferation of glial cells. The roles of calmodulin, calmodulin-dependent kinase II, phospholipase C, protein kinases A and C, and phosphodiesterase in these processes were studied by using their inhibitors: fluphenazine, KN-93, D-609, H89, staurosporine, and papaverine, respectively. PDT-induced firing abolishment was enhanced by H89 or papaverine, whereas staurosporine acted oppositely. Fluphenazine or KN-93 reduced necrosis of neurons and glial cells. H89 enhanced necrosis of neurons, whereas staurosporine enhanced necrosis of glial cells. Inhibition of protein kinases A and C enhanced PDT-induced glial apoptosis. Photodynamic gliosis was prevented by KN-93 or staurosporine. These data indicate possible involvement of calmodulin and calmodulin-dependent kinase II in photoinduced necrosis of neurons and glia. Protein kinase C could protect glial cells from necrosis and apoptosis and participate in photoinduced gliosis and loss of neuronal activity. Protein kinase A maintained neuronal firing and protected neurons from photoinduced necrosis and glial cells from apoptosis. Phosphodiesterase reduced necrosis of photosensitized neurons and glia. Thus, Ca2+- and cAMP-mediated signaling pathways were involved in photooxidative injury of neurons and glia. Their pharmacological modulation may differently change the efficacy of photodynamic injury of neurons and glial cells.17. Fedorenko, G.M., Uzdensky, A.B.Dynamics of ultrastructural changes in the isolated crayfish mechanoreceptor neuron under photodynamic impactJournal of Neuroscience Research 2008 86 (6), pp. 1409-1416 (IF=2,738)ABSTRACT: Photodynamic therapy (PDT) is used for treatment of cancer, including brain tumors. To explore the mechanism of photodynamic injury of neurons, we studied the PDT effect of 10 -7 M Photosens on ultrastructure of isolated crayfish stretch receptor neuron that was used as a model object. After a 5-min treatment that only slightly changed neuron activity, the initial injury (alteration of some mitochondria, vacuolization of the cytoplasm) was observed in parallel with compensatory changes (chromatin decondensation, elongation and aggregation of mitochondria, formation of lysosomes and autophagosomes). Longer photosensitization (30 min) abolished firing, destroyed mitochondria and Golgi apparatus, depleted energy sources (glycogen granules), and impaired granular endoplasmic reticulum and polysomes involved in protein synthesis. Therefore, mitochondria and Golgi apparatus were the primary targets for Photosens-mediated PDT in a single neuron. Their alteration might underlie functional shifts. These structural changes continued to develop after abolishment of neuronal activity and led to necrosis.18. Fedorenko, G.M., Uzdensky, A.B.Ultrastructure of neuroglial contacts in crayfish stretch receptorCell and Tissue Research 2009 337 (3), pp. 477-490 Цит4 (IF=3.114)ABSTRACT: In order to explore neuroglial relationships in a simple nervous system, we have studied the ultrastructure of the crayfish stretch receptor, which consists of only two mechanoreceptor neurons enwrapped by glial cells. The glial envelope comprises 10-30 glial layers separated by collagen sheets. The intercellular space between the neuronal and glial membranes is generally less than 10-15 nm in width. This facilitates diffusion between neurons and glia but restricts neuron communication with the environment. Microtubule bundles passing from the dendrites to the axon through the neuron body limit vesicular transport between the perikaryon and the neuronal membrane. Numerous invaginations into the neuron cytoplasm strengthen glia binding to the neuron and shorten the diffusion pathway between them. Double-membrane vesicles containing fragments of glial, but not neuronal cytoplasm, represent the captured tips of invaginations. Specific triads, viz., "flat submembrane cisterns - vesicles - mitochondria", are presumably involved in the formation of the invaginations and double-membrane vesicles and in neuroglial exchange. The tubular lattice in the glial cytoplasm might transfer ions and metabolites between

the glial layers. The integrity of the neuronal and glial membranes is impaired in some places. However, free neuroglial passage might be prevented or limited by the dense diffuse material accumulated in these regions. Thus, neuroglial exchange with cellular components might be mediated by transmembrane diffusion, especially in the invaginations and submembrane cisterns, by the formation of double-walled vesicles in which large glial masses are captured and by transfer through tubular lattices.19 Lobanov, A.V., Uzdensky, A.B.Protection of crayfish glial cells but not neurons from photodynamic injury by nerve growth factor // Journal of Molecular Neuroscience 2009 39 (1-2), pp. 308-319 Цит8 (IF=2,504)ABSTRACT: Photodynamic treatment that causes intense oxidative stress and cell death is currently used in neurooncology. However, along with tumor cells, it may damage healthy neurons and glia. In order to study photodynamic effect on normal nerve and glial cells, we used crayfish stretch receptor, a simple system consisting of only two identified sensory neurons surrounded by glial cells. Photodynamic treatment induced firing abolition and necrosis of neurons as well as necrosis and apoptosis of glial cells. Nerve growth factor but not brain-derived neurotrophic factor or epidermal growth factor protected glial cells but not neurons from photoinduced necrosis and apoptosis. Inhibitors of tyrosine kinases or protein kinase JNK eliminated anti-apoptotic effect of nerve growth factor in photosensitized glial cells but not neurons. Therefore, these signaling proteins were involved in the anti-apoptotic activity of nerve growth factor. These data indicate the possible presence of receptors capable of recognizing murine nerve growth factor in crayfish glial cells. Thus, intercellular signaling mediated by nerve-growth-factor-like neurotrophin, receptor tyrosine kinase, and JNK may be involved in crayfish glia protection from apoptosis induced by photodynamic treatment. 20. Fedorenko, G.M., Fedorenko, Y.P., Fedorenko, A.G., Uzdensky, A.B.Dynamics of ultrastructural alterations in photosensitized crayfish glial and neuronal cells: Structures involved in transport processes and neuroglial interactions // Journal of Neuroscience Research 201189 (3), pp. 341-351 (IF=2,738)  ABSTRACT: Photodynamic therapy (PDT) is used for cancer treatment, including brain tumors. To explore the dynamics of photodynamic injury of glial cells and neurons and corresponding neuroglial interactions, we studied ultrastructure of the PDT-treated crayfish stretch receptor that consists of a single sensory neuron enwrapped by glial cells. Just after PDT, swelling of some mitochondria, dictyosomes, and endoplasmic reticulum cisterns occurred in neurons and glial cells. Tubular lattices involved in intraglial transport became swollen and disintegrated. At 1 hr postirradiation, these alterations were expanded to the whole cells. Segregation of the neuronal cytoplasm by Nissl bodies, which were involved in protein synthesis and transport along neurites, was lost. Swelling of submembrane cisterns prevented formation of glial protrusions and double-wall vesicles involved in the glia-to-neuron transport. Five hours later, glial layers lost organelles, stuck together, or dilated locally as a result of edema. In the neuronal cytoplasm, only demises of ER and swollen mitochondria were present, but few mitochondria retained normal structure. Thus, swelling of intracellular organelles, the first sign of photodynamic injury, occurred simultaneously in neurons and glia, but glial organelles were eliminated more quickly. Therefore, glial cells were less resistant to PDT than neurons. Adjacent glial layers were damaged less than remote ones, suggesting their protection by the neuron. The structures involved in glia-to-neuron (neuronal submembrane cisterns, glial protrusions, double-wall vesicles), intraglial (tubular lattices), and intraneuronal (Nissl bodies, Golgi apparatus, microtubular bundles) transport were impaired at the earlier stages of stretch receptor damage21. Komandirov, M.A., Knyazeva, E.A., Fedorenko, Y.P., Rudkovskii, M.V., Stetsurin, D.A., Uzdensky, A.B.On the role of phosphatidylinositol 3-kinase, protein kinase B/Akt, and glycogen synthase kinase-3β in photodynamic injury of crayfish neurons and glial cells // Journal of Molecular Neuroscience 2011 45 (2) pp. 229-235 Цит. 8 (IF=2,504)ABSTRACT: Photodynamic treatment that causes intense oxidative stress and cell death is currently used in neurooncology. However, along with tumor cells, it may damage healthy neurons and glia. To study the involvement of signaling processes in photodynamic injury or protection of neurons and glia, we used crayfish mechanoreceptor consisting of a single neuron surrounded by glial cells. It was photosensitized with alumophthalocyanine Photosens. Application of specific inhibitors showed that phosphatidylinositol

3-kinase did not participate in photoinduced death of neurons and glia. Akt was involved in photoinduced necrosis but not in apoptosis of neurons and glia. Glycogen synthase kinase-3β participated in photoinduced apoptosis of glial cells and in necrosis of neurons. Therefore, phosphatidylinositol 3-kinase/protein kinase Akt/glycogen synthase kinase-3β pathway was not involved as a whole in photodynamic injury of crayfish neurons and glia but its components, Akt and glycogen synthase kinase-3β, independently and cell specifically regulated death of neurons and glial cells. According to these data, necrosis in this system was a controlled but not a non-regulated cell death mode. The obtained results may be used for the search of pharmacological agents selectively modulating death and survival of normal neurons and glial cells during photodynamic therapy of brain tumors.22. Uzdensky, A., Kristiansen, B., Moan, J., Juzeniene, A.Dynamics of signaling, cytoskeleton and cell cycle regulation proteins in glioblastoma cells after sub-lethal photodynamic treatment: Antibody microarray study // Biochimica et Biophysica Acta - General Subjects 2012 1820 (7), pp. 795-803 (IF=5.0)ABSTRACT: Background: Photodynamic therapy (PDT) that induces oxidative stress and cell death is used for tumor destruction in oncology. To characterize early molecular events in photosensitized glioblastoma cells, we studied expression of 224 proteins after sublethal PDT that doesn't kill but wounds cells. Methods: Cultured glioblastoma D54Mg cells were photosensitized with 5-aminolevulinic acid so that cell survival was 95-100%. At following 0.5-5.5 h protein expression and phosphorylation was assayed using proteomic antibody microarrays. Results: Within the first post-treatment hour we observed phosphorylation of protein kinase Raf, adhesion-related kinases FAK and Pyk2, and microtubule-associated protein tau. Protein kinase Cγ and microtubule-associated protein MAP-1B were overexpressed. Dystrophin, calponin, and vinculin, components of the actin cytoskeleton scaffold, microtubule-associated proteins MAP2 and CNP, cytokeratins 4 and 7 were down-regulated that indicated changes in adhesion and cell shape. Down-regulation of cyclins A, D1 and D3, c-Myc, checkpoint proteins chk1/2 and up-regulation of Smad4 could arrest the cell cycle. Overexpression of Bcl-xL and down-regulation of caspase 9 demonstrated anti-apoptotic response. At 2 h post-treatment protein expression changed lesser but at 5.5 h levels of PKCγ and β-synuclein and phosphorylation of Raf, FAK, Pyk2, and tau increased again. Conclusions: Sub-lethal PDT induces complex response of glioblastoma cells including changes in activity and expression of proteins involved in adhesion-mediated signaling, signal transduction, cytoskeleton remodeling, cell cycle regulation and anti-apoptotic processes. General significance: Multiple reactions of various cellular subsystems including adhesion, cytoskeleton, signal transduction, cell cycle, and apoptosis are integrated into the general cell response to a sublethal impact.23. Uzdensky, A., Komandirov, M., Fedorenko, G., Lobanov, A.Protection Effect of GDNF and Neurturin on Photosensitized Crayfish Neurons and Glial Cells // Journal of Molecular Neuroscience 2012, pp. 1-11 (IF=2,504)ABSTRACT: Neurons and glial cells can protect each other from stress and following death by mutual exchange with neurotrophins. In order to examine involvement of different neurotrophic factors in neuroglial interactions in a photosensitized crayfish stretch receptor, a simple model object consisting of only two sensory neurons enveloped by glial cells, we studied the influence of glial cell line-derived neurotrophic factor (GDNF), neurturin, and ciliary neurotrophic factor (CNTF) on its photodynamic injury. Photodynamic treatment, which causes strong oxidative stress, induced firing abolition and necrosis of neurons, necrosis, and apoptosis of glial cells. GDNF significantly reduced photoinduced neuronal necrosis and neurturin but not CNTF showed a similar tendency. Both of them significantly reduced necrosis and apoptosis of glial cells. At the ultrastructural level, neurons and glial cells treated with GDNF in the darkness contained large mitochondria with well-developed cristae, numerous ribosomes, polysomes, rough endoplasmic reticulum (ER), and dictyosomes. This indicated the high level of bioenergetic, biosynthetic, and transport processes. Photodynamic treatment caused swelling and vacuolization of mitochondria, dictyosomes, and ER. It also impaired formation of glial protrusions and double membrane vesicles that transfer glial material into the neuron. GDNF prevented photoinduced mitochondria swelling that disturbed the cellular bioenergetics and cytoplasm vacuolization associated with injury of intracellular organelles. It also preserved the structures involved in protein synthesis and transport: rough ER, dictyosomes, polysomes, microtubule bundles, submembrane cisterns, and double membrane vesicles.

GDNF-mediated maintenance of metabolism and ultrastructure of photosensitized neurons and glial cells may be the basis of its neuro- and glia protective effects

Svetlana RAEVSKAYA (h=9) . 2003-2012 publications. 1.A.M. Pugachev, V.I. Kovalevskii, N.V. Surovtsev, S.Kojima, S.A. Prosandeev, I.P. Raevski, and S.I. Raevskaya, Broken Local Symmetry in Paraelectric BaTiO3Proved by Second Harmonic Generation // Phys.Rev.Lett. 2012. v. 108, No. 24, 247601. 1-5. (IF= 7.37).ABSTRACT: Precursor dynamics of a cubic to tetragonal ferroelectric phase transition in BaTiO3 is studied by the accurate measurement of the second harmonic generation (SHG) integral intensities. A finite signal holds for the SHG integrated intensity above the ferroelectric Curie temperature Tc = 403 K. Above the Burn’s temperature Td = 580 K, the power law with the exponent γ =1 shows normal SHG nature originating from the hyper-Raman scattering by dynamical polar excitations, while, below Td, a SHG signal from polar nanoregions becomes dominant with the larger exponent γ = 2. Such a crossover of the power law exponent near Td is discussed on the basis of the effective Hamiltonian method and Monte Carlo simulation.2.I. P. Raevski, S. P. Kubrin, S. I. Raevskaya, D. A. Sarychev, S. A. Prosandeev, and M. A. Malitskaya, Magnetic Properties of PbFe1/2Nb1/2O3: Mossbauer Spectroscopy and First Principles Calculations // Phys.Rev.B. 2012. V.85, No. 22, 224412. 1-5. (IF= 3.69).ABSTRACT: Magnetic properties of magnetoelectric PbFe1/2Nb1/2O3 (PFN) have been studied with the help of Mossbauer spectroscopy. In contrast to the belief that Nb and Fe are randomly distributed in the lattice, we found that the Fe ions occupy two crystallographic positions, which differ by the quadrupole splitting and magnetic field mirroring the difference in the nearest neighbor environment of the Fe ions. The ratio of the weights of these positions is 2.3, at 14 K. First-principles calculations provide a microscopic insight of this finding.3.R.A. Shakhovoy, S.I. Raevskaya, L.A. Shakhovaya, D.V. Suzdalev, I.P. Raevski, Yu.I. Yuzyuk, A.F. Semenchev and M. El Marssi. Ferroelectric Q-phase in oxygen-deficient single crystals of antiferroelectric NaNbO3: dielectric, dilatometric and micro-Raman studies // Journal of Raman Spectroscopy. 2012. V.43, № 8, P.1141–1145. (IF= 3.087).ABSTRACT: Micro-Raman studies of oxygen-deficient gray-colored NaNbO3 single crystals have shown that at room temperature both antiferroelectric P and ferroelectric Q phases are present simultaneously as separate regions tens of micrometers in size. Phase transitions in P and Q regions have been elucidated by dielectric, dilatometric and micro-Raman studies. For the first time, the sequence of phase transitions between antiferroelectric phase P and ferroelectric Q and N phases has been revealed.4.I.P. Raevski, S.P. Kubrin, S.I. Raevskaya, S.A. Prosandeev, M.A. Malitskaya, V.V. Titov, D. A. Sarychev, A.V. Blazhevich, and I.N. Zakharchenko. Dielectric and Mossbauer Studies of Ferroelectric and Magnetic Phase Transitions in A-Site and B-Site Substituted Multiferroic PbFe0.5Nb0.5O3. // IEEE Trans. Ultrason. Ferroelect. Freq. Contr. 2012. V.59, No.9. P. 1872-1878.(IF= 1.694).ABSTRACT: In the present study, we diluted either A- or B- sublattice of perovskite multiferroic PbFe0.5Nb0.5O3 (PFN) and studied the changes of the magnetic and ferroelectric phase transition temperatures and dielectric properties caused by such dilution. Dielectric studies of PFN single crystals show that, in contrast to the commonly adopted view, the ferroelectric phase transition in PFN is non-diffused and the relaxor-like behavior usually observed in ceramic samples has an extrinsic nature. A-site substitutions (Ba, Ca) lead to the smearing of the permittivity-temperature maximum, lowering its maximum temperature, Tm and inducing relaxor behavior.B-site diluting of PFN by Ti increases Tm and only slightly affects the permittivity maximum diffuseness. Both A-site and B-site substitutions in PFN lead to lowering of its Néel temperature, TN. However, above a certain compositional threshold, fast lowering of TN stops and a new magnetic state with comparatively high (~50K) transition temperature becomes stable in a rather wide compositional range.5.J. Zhai, H. Chen, C.C. Chou, S.I. Raevskaya, S.A. Prosandeev, I.P. Raevski. Peculiarities of Temperature and Field Dependence of Tunability in Ba0.6Sr0.4TiO3 Ceramics with Differing Grain Sizes // J. of Alloys and Compounds, 2011. V.509, No 20. P.6113-6116. (IF= 2.289).

ABSTRACT: Study of the dielectric tunability and susceptibility, in a wide temperature range and at different biasfields, in Ba0.6Sr0.4TiO3 (BST) sol–gel derived ceramics of different crystallite sizes (between 1 and 6 μm),establishes two new regularities. The first one concerns the relative temperature of the maxima positions of the tunability and susceptibility. We show that the maximum in tunability is always at lower temperatures compared to the maximum in susceptibility. The second regularity tells that the electric field dependence of the susceptibility maximum temperature is always stronger than the one for the tunability maximum temperature. In small-size crystallite BST ceramics the temperature of susceptibility maximum starts changing only above a certain threshold field. Additionally, we discuss the nature of an extrinsic contribution to tunability in small-size crystallite BST ceramics.6.I. K. Bdikin, J. Gracio, D. A. Kiselev, I. P. Raevski, S. I. Raevskaya, S.A.Prosandeev, A. L. Kholkin. Engineering of local domains in relaxor 0.77PbMg1/3Nb2/3O3-0.23PbSc1/2Nb1/2O3 single crystals // J. Appl.Phys. 2011. Vol.110, № 5. P. 052002. 1-5. (IF= 2.169).ABSTRACT: We used piezoresponse force microscopy (PFM) to study the dc bias field-induced domain structure of the (001) oriented single crystals of 0.77 Pb(Mg1/3Nb2/3)O3-0.23PbSc1/2Nb1/2O3 relaxor. In the as-grown state, no polarization contrast was observed due to the average cubic symmetry of the crystal. Upon application of a dc bias applied via a PFM tip, a stable complex domain pattern, corresponding to a hedgehog-type topological defect, appeared on the surface of the crystal. The shape of these domains depended on the magnitude of the field. If the field was below a threshold, the domains possessed a cylindrical form. Above the threshold, the border between domains became close to a straight line. At high biases and large separation between the pulses, the development of the domains obeyed an avalanche-type dynamics.7.E.I.Sitalo, I.P. Raevski, A.G. Lutokhin, A.V. Blazhevich, S.P. Kubrin, S.I. Raevskaya, Yu.N. Zakharov, M.A. Malitskaya, V.V. Titov, I.N. Zakharchenko Dielectric and Piezoelectric Properties of PbFe1/2Nb1/2O3–PbTiO3 Ceramics From the Morphotropic Phase Boundary Compositional Range // IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2011, v.58, No.9. P. 1914 – 1919. (IF= 1.694).ABSTRACT: Dielectric, X-ray, and piezoelectric studies of highly-resistive Li-doped (1−x)PbFe1/2Nb1/2O3–(x)PbTiO3 (PFN-xPT) ceramics from the 0 ≤ x ≤ 0.2 range fabricated by solid-state synthesis and usual sintering have been carried out. Distinct anomalies of dielectric and piezoelectric parameters, corresponding to the transition between rhombohedral (monoclinic) and tetragonal ferroelectric phases, have been observed in pure PFN and PFN-xPT compositions with PbTiO3 content up to 8 mol.%. The x,T-phase diagram of the PFN-xPT solid solution system has been constructed using these data.8. Yu.I. Yuzyuk, R.A. Shakhovoy, S.I. Raevskaya, I.P. Raevski, M. El Marssi and M.G. Karkut.Ferroelectric Q-phase in a NaNbO3 epitaxial thin film – Appl.Phys.Lett. 2010. V.96, №22. P.222904-1-222904-3 (IF= 3.787).ABSTRACT: Epitaxial NaNbO3 thin films have been grown by pulsed laser deposition on cubic (00l) MgOsubstrate with epitaxial La0.5Sr0.5CoO3 buffer layer. Micro-Raman spectroscopy studies revealed that the ferroelectric Q phase (Pmc21, Z=4) is stable in a 250-nm-thick film in contrast to the antiferroelectric phase P (Pbma, Z=8) known to exist in the bulk single crystals and ceramics of undoped stoichiometric NaNbO3. Temperature-dependent Raman spectra indicate that the Q phase is stable over a wide temperature range (at least from 80 to 600 K), while the low-temperature ferroelectric rhombohedral phase N, typical for NaNbO3 single crystals, is not observed.9. V.V. Laguta, J. Rosa, L. Jastrabik, R. Blinc, P. Cevc, B. Zalar, M. Remskar, S.I. Raevskaya, and I.P. Raevski. 93Nb NMR and Fe3+ EPR study of local magnetic properties of disordered magnetoelectric PbFe1/2Nb1/2O3 // Materials Research Bulletin. 2010.v.45, No.11. P.1720-1727. (IF= 2.108).ABSTRACT: The 93Nb NMR and Fe3+ EPR spectra of a magnetoelectric PbFe1/2Nb1/2O3 (PFN) single crystal as well as of PFN ceramics and nanopowder have been measured. The relation between the chemical disorder and the local magnetic structure has been determined. The data show the occurrence of an antiferromagnetic (AFM) phase transition at 145 and 135 K in both single crystal and ceramic samples, respectively. The AFM phase transition is however essentially smeared out in the nanopowder. Two

different Nb sites exist which have different local magnetic fields which are essentialy distributed in value. These two Nb sites correspond to different types of ‘‘chemical’’ order: Fe rich, Nb poor and Fe poor, Nb rich regions. The temperature dependences of the sublattice magnetizations and the values of the superhyperfine fields at the Nb ions are obtained. NMR data suggest that a spin–glass like state of PFN below T = 20 K arises from the Fe poor, Nb rich regions.10. I. P. Raevski, S. P. Kubrin, S. I. Raevskaya, V. V. Titov, D. A. Sarychev, M. A. Malitskaya, I. N. Zakharchenko, and S. A. Prosandeev. Experimental evidence of the crucial role of nonmagnetic Pb cations in the enhancement of the Néel temperature in perovskite Pb1−xBaxFe1/2Nb1/2O3 // Phys. Rev. B 2009. V.80, № 2. P.024108-1 -024108-6. (IF= 3.69).ABSTRACT: Our experimental study of Pb1−xBaxFe1/2Nb1/2O3 shows that, the Néel temperature in this solid solution drops down at x=0.15/ 0.20, and, at the same threshold, the polarization also looses its long-range order. Thus, the multifunctional solid solution studied demonstrates a possibility of simultaneous controlling the magnetic and ferroelectric properties by changing the concentration of only lead, which is a nonmagnetic ion.11. S. I. Raevskaya, I. P. Raevski, S. P. Kubrin, M. S. Panchelyuga, V. G. Smotrakov, V. V. Eremkin, S. A. Prosandeev. Quantum paraelectricity coexisting with a ferroelectric metastable state in single crystals of NaNbO3: a new quantum effect //J. Phys. Condens. Matter. 2008. V.20, №23.- P.232202. 1-5. (IF= 2.332).ABSTRACT: We experimentally show that, in contrast to the data having been collected so far, some single crystals of NaNbO3 exhibit a dielectric permittivity of several thousand, at low T , and this value is saturated when approaching 0 K on cooling. Other sodium niobate crystals (having larger dielectric losses) present a first-order phase transition to a ferroelectric phase on cooling (at 80–200 K). The dielectric permittivity at the phase transition obtained on cooling shows a tendency to increase and saturate, when the thermal hysteresis increases. We identify the ground state of the sodium niobate crystal exhibiting the smallest dielectric losses (in the studied set of crystals) as a novel quantum paraelectric state coexisting with a metastable ferroelectric state. In principle, the crystal presenting the state of quantum paraelectricity can be considered as having the largest (among the crystals studied)thermal hysteresis, for which the low boundary is below 0 K.12. S. I. Raevskaya, Yu. N. Zakharov, A. G. Lutokhin, A. S.Emelyanov, I. P. Raevski, M. S. Panchelyuga, V. V. Titov, and S. A. Prosandeev. Critical nature of the giant field-induced pyroelectric response in Pb(Mg1/3Nb2/3)O3–xPbTiO3 single crystals // Appl. Phys. Lett. 2008. V.93. № 4.- P. 042903.1-3. (IF= 3.787).ABSTRACT: We study the E-T phase diagram and dynamical pyroelectric coefficient of an (001)-oriented flux-grown 0.8 Pb(Mg1/3Nb2/3)O3–0.2PbTiO3 single crystal. We found that the highest pyroelectric coefficient can be achieved at the point having quasicritical features. These data establish a quasicritical behavior of the field-induced pyroelectric coefficients in relaxors.13. S. Prosandeev. M. Panchelyuga, S. Raevskaya, I. Raevski, Theory of the dielectric nonlinearity in ferroelectric relaxors in the vicinity of the Vogel-Fulcher temperature under dc bias fields // Appl. Phys. Lett. 2007. V.91. № 24.- P. 242904.1-3.(IF= 3.787).ABSTRACT: Usually, dipole glass phase transitions are associated with the divergence of the third harmonic of the dielectric response. We show that, in reality, (i) random fields diffuse this singularity; (ii)even if the random field is absent, the divergence is one sided (it exists only at the temperatures, which are lower than the Vogel-Fulcher temperature); (iii) in the latter case, the divergence is followed by a jump of the first and third harmonics; and (iv) if the bias field exceeds the random field, all dielectric anomalies must be seen well.14. S. I. Raevskaya, A. S. Emelyanov, F. I. Savenko, M. S. Panchelyuga, I. P. Raevski, S. A. Prosandeev, Eugene V. Colla, Haydn Chen, S. G. Lu, R. Blinc, Z. Kutnjak, P. Gemeiner, B. Dkhil, L. S. Kamzina. Quasivertical line in the phase diagram of single crystals of PbMg1/3Nb2/3O3−(x)PbTiO3 (x=0.00, 0.06, 0.13 and 0.24) with a giant piezoelectric effect //Phys.Rev.B. 2007. V.76. 060101. 1-4. (IF= 3.69).ABSTRACT: We show that the phase diagram of the (001) Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-xPT) (x=0.00, 0.06, 0.13, and 0.24) and (111) PMN-0.24PT lead-magnesium niobate mixed with lead titanate possesses a quasivertical

line in the E electric field – T temperature plot, which hardly depends on the field. The existence of this linehas been confirmed by independent studies of single crystals grown in different laboratories, by measuring thedielectric permittivity, compliances, and optical transmission, also in different laboratories. A thermal hysteresisinherent to first order phase transitions complicates the phase diagram. The piezoelectric coefficients of the(001) PMN-xPT (x =0.06 and 0.13) have two peaks versus temperature, at finite fields. The first peak is dueto the quasivertical phase boundary. The second is in the vicinity of a turning point of the Tm(E) temperatureof the dielectric permittivity diffuse maximum. We show that the second peak prevails at reasonable fields, andthe piezoelectric coefficients have comparatively large values at this peak, even at small x.15. A.S. Emelyanov, S.I. Raevskaya, F.I. Savenko, V.Yu. Topolov, I.P. Raevski, A.V. Turik, A.L. Kholkin. Dielectric and piezoelectric properties of (001)-oriented (1 − x)Pb(Mg1/3Nb2/3)O3 –xPbTiO3 single crystals with 0.1≤ x ≤ 0.4 // Solid State Commun. 2007.-V.143, №3.- P.188–192. (IF= 1.839).ABSTRACT: Temperature and compositional dependences of the piezoelectric coefficient d33 and dielectric permittivity for (001)-oriented (1 − x) Pb(Mg1/3Nb2/3)O3-xPbTiO3 flux-grown single crystals have been studied in the wide compositional range (0.10 < x < 0.40). The effect of multiple configurations of the 71 (109) domains existing in the ferroelectric 3m phase on the apparent values of d33 and ε33 for composition x = 0.33 close to the morphotropic phase boundary is considered. The results obtained enable one to better define the compositional dependence d33(x) and to interpret inconsistencies in d33 values reported in the literature.16 .Raevski I. P., Prosandeev S. A., Emelyanov A. S., Raevskaya S.I., Colla E. V., Viehland D., Kleemann W., Vakhrushev S. B., Dellis J-L., El Marssi M., Jastrabik L. Bias field effect on the temperature anomalies of dielectric permittivity in PbMg1/3Nb2/3O3- PbTiO3 single crystals //Phys. Rev. 2005. V. B72. № 18. P.184104-1 - 184104-8. (IF= 3.69).ABSTRACT: In contrast to ordinary ferroelectrics where the temperature Tm of the permittivity maximum monotonically increases with bias field E in (1 − x) Pb(Mg1/3Nb2/3)O3-xPbTiO3 (0<x<0.35) single crystals, Tm was found to remain constant or to decrease with E up to a certain threshold field Et, above which Tm starts increasing. The threshold field Etdecreases with increasing x, tending toward zero at approximately x=0.4. We explain thisdependence in the framework of models which take into account quenched random fields and random bonds.For crystals with 0.06<x<0.13, the E-T phase diagrams are constructed. 17.Yuzyuk Yu. I., Simon P., Gagarina E., Hennet L., Thiaudière D., Torgashev V.I., Raevskaya S.I., Raevskii I.P., Reznitchenko L.A., Sauvajol J. L. Modulated phases in NaNbO3: Raman scattering, synchrotron x-ray diffraction, and dielectric investigations // J.Phys: Condens. Matter. 2005. V.17. № 33. P.4977-4990. (IF= 2.018).ABSTRACT: Raman spectra of sodium niobate (NaNbO3) were obtained in all phases and revealed a significant disorder in the high-temperatureU, T2 and T1 phases and a complicated folding of the Brillouin zone at the transitions into modulated S, R, P and N phases associated with the competitive zone-boundary soft modes (in-phase and out-of phase octahedral tilts) along the M–T–R line. An extensive Raman study combined with x-ray diffraction (XRD) and dielectric measurements confirmed the presence of the incommensurate (INC) phase in sodium niobate.18.Raevski I. P., Raevskaya S.I., Prosandeev S. A., Shuvaeva V.A., Glazer A.M., Prosandeeva M. S., Diffuse first-order phase transition in NaNbO3:Gd // J.Phys: Condens. Matter . 2004. V.16, №15. P.L221-L226. (IF= 2.018).ABSTRACT: Dielectric permittivitymeasurements showthat (1−x)NaNbO3–(x)Gd1/3NbO3 crystals, at x = 0.09, exhibit a first-order phase transition near 150 ◦C that is diffuse over a wide temperature interval. The area of the ε(T)

thermal hysteresis loop was found to depend both on annealing and cooling temperatures. Optical studies in polarized light show a decrease of the domain sizes at this phase transition. The results obtained are fitted assuming a spatial distribution of Curie temperatures.19.Raevski I.P., Reznitchenko L.A., Malitskaya M.A., Shilkina L.A., Lisitsina S.O., Raevskaya S.I., Kuznetsova E.M. NaNbO3 –based relaxor // Ferroelectrics .-2004.- V.299, №1-4.-P.95-101. (IF= 0.447).ABSTRACT: Binary NaNbO3-ABO3 perovskite solid solutions belonging to the group II according to N.N. Krainik classification (Izv.Akad. Nauk SSSR, Ser. Phys. 28, 643 (1964)) exhibit a relaxor-type behavior when the second component concentration exceeds a threshold value x0, corresponding to the abrupt decrease of the dielectric permittivity ε maximum temperature Tm. The Tm values of all the known binary NaNbO3-ABO3 relaxorcompositions are well below the room temperature and the maximal ε values εm are much lower than in the case of Pb-containing relaxors. However both Tm and εm values may be increased substantially by Li or K-doping leading to the formation of ternary NaNbO3-ABO3-LiNbO3 (KNbO3) solid solutions.20.Bokov A.A., BingY.-H., Chen W., Ye Z.-G., Bogatina S. A., Raevski I. P., Raevskaya S. I., Sahkar E.V. Empirical scaling of the dielectric permittivity peak in relaxor ferroelectrics //Phys.Rev.B. 2003. V.68. № 5. 052102. 1-4. (IF= 3.69).ABSTRACT: Dielectric permittivity ε as a function of temperature is measured in PbMg1/3Nb2/3O3 and a number of other relaxor ferroelectrics with the perovskite structure. It is found that the data taken from the high-temperatureslopes of the diffused permittivity peaks of all the materials studied can be collapsed onto a single scaling line. This formula describes the static conventional relaxor susceptibility, which provides the dominant contribution to the permittivity peak at temperatures above the temperature of the maximum. In the close vicinity of the peak temperature and below, the scaling is disturbed due to the conventional relaxor dispersion.

Igor RAEVSKI (h=17)1. A.M. Pugachev, V.I. Kovalevskii, N.V. Surovtsev, S.Kojima, S.A. Prosandeev, I.P. Raevski, and S.I. Raevskaya, Broken Local Symmetry in Paraelectric BaTiO3Proved by Second Harmonic Generation // Phys.Rev.Lett. 2012. v. 108, No. 24, 247601. 1-5. (IF= 7.37).ABSTRACT: Precursor dynamics of a cubic to tetragonal ferroelectric phase transition in BaTiO3 is studied by the accurate measurement of the second harmonic generation (SHG) integral intensities. A finite signal holds for the SHG integrated intensity above the ferroelectric Curie temperature Tc = 403 K. Above the Burn’s temperature Td = 580 K, the power law with the exponent γ =1 shows normal SHG nature originating from the hyper-Raman scattering by dynamical polar excitations, while, below Td, a SHG signal from polar nanoregions becomes dominant with the larger exponent γ = 2. Such a crossover of the power law exponent near Td is discussed on the basis of the effective Hamiltonian method and Monte Carlo simulation.2. I. P. Raevski, S. P. Kubrin, S. I. Raevskaya, D. A. Sarychev, S. A. Prosandeev, and M. A. Malitskaya, Magnetic Properties of PbFe1/2Nb1/2O3: Mossbauer Spectroscopy and First Principles Calculations // Phys.Rev.B. 2012. V.85, No. 22, 224412. 1-5. (IF= 3.69).ABSTRACT: Magnetic properties of magnetoelectric PbFe1/2Nb1/2O3 (PFN) have been studied with the help of Mossbauer spectroscopy. In contrast to the belief that Nb and Fe are randomly distributed in the lattice, we found that the Fe ions occupy two crystallographic positions, which differ by the quadrupole splitting and magnetic field mirroring the difference in the nearest neighbor environment of the Fe ions. The ratio of the weights of these positions is 2.3, at 14 K. First-principles calculations provide a microscopic insight of this finding.3. R.A. Shakhovoy, S.I. Raevskaya, L.A. Shakhovaya, D.V. Suzdalev, I.P. Raevski, Yu.I. Yuzyuk, A.F. SemenchevandM. ElMarssi. Ferroelectric Q-phase in oxygen-deficient single crystals of antiferroelectric NaNbO3: dielectric, dilatometric and micro-Raman studies // Journal of Raman Spectroscopy. 2012. V.43, № 8, P.1141–1145. (IF= 3.087).ABSTRACT: Micro-Raman studies of oxygen-deficient gray-colored NaNbO3 single crystals have shown that at room temperature both antiferroelectric P and ferroelectric Q phases are present simultaneously as

separate regions tens of micrometers in size. Phase transitions in P and Q regions have been elucidated by dielectric, dilatometric and micro-Raman studies. For the first time, the sequence of phase transitions between antiferroelectric phase P and ferroelectric Q and N phases has been revealed.4. I.P. Raevski, S.P. Kubrin, S.I. Raevskaya, S.A. Prosandeev, M.A. Malitskaya, V.V. Titov, D. A. Sarychev, A.V. Blazhevich, and I.N. Zakharchenko. Dielectric and Mossbauer Studies of Ferroelectric and Magnetic Phase Transitions in A-Site and B-Site Substituted Multiferroic PbFe0.5Nb0.5O3. // IEEE Trans. Ultrason. Ferroelect. Freq. Contr. 2012. V.59, No.9. P. 1872-1878. (IF= 1.694).ABSTRACT: In the present study, we diluted either A- or B- sublattice of perovskite multiferroic PbFe0.5Nb0.5O3 (PFN) and studied the changes of the magnetic and ferroelectric phase transition temperatures and dielectric properties caused by such dilution. Dielectric studies of PFN single crystals show that, in contrast to the commonly adopted view, the ferroelectric phase transition in PFN is non-diffused and the relaxor-like behavior usually observed in ceramic samples has an extrinsic nature. A-site substitutions (Ba, Ca) lead to the smearing of the permittivity-temperature maximum, lowering its maximum temperature, Tm and inducing relaxor behavior.B-site diluting of PFN by Ti increases Tm and only slightly affects the permittivity maximum diffuseness. Both A-site and B-site substitutions in PFN lead to lowering of its Néel temperature, TN. However, above a certain compositional threshold, fast lowering of TN stops and a new magnetic state with comparatively high (~50K) transition temperature becomes stable in a rather wide compositional range.5. V. I. Aleshin, and I. P. Raevski. Negative Poisson’s ratio and piezoelectric anisotropy of tetragonal ferroelectric single crystals // J. Appl.Phys..2012. V.111, No.11, 114101(8 pp). (IF= 2.169).ABSTRACT: Orientational dependences of the Poisson’s ratio have been calculated for several perovskitetetragonal ferroelectric singe crystals: 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3, PbTiO3, and BaTiO3. All these crystals are shown to have negative values of Poisson’s ratio in some crystallographic directions thus being so-called partial auxetics. The largest negative Poisson’s ratio values possess 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 single crystals. The thermodynamic restrictions for the d33 and d31 piezoelectric moduli of the tetragonal crystals have been revealed. The relation between Poisson’s ratio and piezoelectric properties of perovskite tetragonal ferroelectric singe crystals is discussed.6. A.T. Kozakov, A.G. Kochur, K.A. Googlev, A.V. Nikolsky, I.P.Raevski, V.G. Smotrakov, V.V.Yeremkin. X-ray photoelectron study of the valence state of iron in iron-containing single-crystal (BiFeO3, PbFe1/2Nb1/2O3), and ceramic (BaFe1/2Nb1/2O3) multiferroics // Journal of Electron Spectroscopy and Related Phenomena, 2011.V.184, Issues 1-2, рр.16-23. (IF= 1.482).ABSTRACT: Fe2p, Fe3p, and Fe3s X-ray photoelectron spectra (XPS) are measured with high resolution in singlecrystal multiferroics BiFeO3 and PbFe1/2Nb1/2O3, as well as in reference samples Fe2O3, FeSO4·7H2O,FeC2O4·2H2O. The spectra are assigned based on an isolated-ion approximation calculation. Single-crystalmultiferroics and Fe2O3 are shown to have the Fe ions only in the Fe3+ valence state. Ceramic samplesof BaFe1/2Nb1/2O3 with various relative Fe2+/Fe3+ abundances are synthesized in various conditions. Anapproximate method to determine the Fe2+/Fe3+ratio in a sample is suggested. The method is based onthe fitting of the sample’s 2p XPS with a superposition of Fe2+ and Fe3+ 2p spectra. An effect of temperatureregimes of sintering and annealing on the Fe2+/Fe3+ ratio is demonstrated.7. J. Zhai, H. Chen, C.C. Chou, S.I. Raevskaya, S.A. Prosandeev, I.P. Raevski. Peculiarities of Temperature and Field Dependence of Tunability in Ba0.6Sr0.4TiO3 Ceramics with Differing Grain Sizes // J. of Alloys and Compounds, 2011. V.509, No 20. P.6113-6116. (IF= 2.289).ABSTRACT: Study of the dielectric tunability and susceptibility, in a wide temperature range and at different biasfields, in Ba0.6Sr0.4TiO3 (BST) sol–gel derived ceramics of different crystallite sizes (between 1 and 6 μm),establishes two new regularities. The first one concerns the relative temperature of the maxima positions of the tunability and susceptibility. We show that the maximum in tunability is always at lower temperatures compared to the maximum in susceptibility. The second regularity tells that the electric field dependence of the susceptibility maximum temperature is always stronger than the one for the tunability maximum

temperature. In small-size crystallite BST ceramics the temperature of susceptibility maximum starts changing only above a certain threshold field. Additionally, we discuss the nature of an extrinsic contribution to tunability in small-size crystallite BST ceramics.8. I. K. Bdikin, J. Gracio, D. A. Kiselev, I. P. Raevski, S. I. Raevskaya, S.A.Prosandeev, A. L. Kholkin. Engineering of local domains in relaxor 0.77PbMg1/3Nb2/3O3-0.23PbSc1/2Nb1/2O3 single crystals // J. Appl.Phys. 2011. Vol.110, № 5. P. 052002. 1-5. (IF= 2.169).ABSTRACT: We used piezoresponse force microscopy (PFM) to study the dc bias field-induced domain structure of the (001) oriented single crystals of 0.77 Pb(Mg1/3Nb2/3)O3-0.23PbSc1/2Nb1/2O3 relaxor. In the as-grown state, no polarization contrast was observed due to the average cubic symmetry of the crystal. Upon application of a dc bias applied via a PFM tip, a stable complex domain pattern, corresponding to a hedgehog-type topological defect, appeared on the surface of the crystal. The shape of these domains depended on the magnitude of the field. If the field was below a threshold, the domains possessed a cylindrical form. Above the threshold, the border between domains became close to a straight line. At high biases and large separation between the pulses, the development of the domains obeyed an avalanche-type dynamics.9. E.I.Sitalo, I.P. Raevski, A.G. Lutokhin, A.V. Blazhevich, S.P. Kubrin, S.I. Raevskaya, Yu.N. Zakharov, M.A. Malitskaya, V.V. Titov, I.N. Zakharchenko Dielectric and Piezoelectric Properties of PbFe1/2Nb1/2O3–PbTiO3 Ceramics From the Morphotropic Phase Boundary Compositional Range // IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2011, v.58, No.9. P. 1914 – 1919. (IF= 1.694).ABSTRACT: Dielectric, X-ray, and piezoelectric studies of highly-resistive Li-doped (1−x)PbFe1/2Nb1/2O3–(x)PbTiO3 (PFN-xPT) ceramics from the 0 ≤ x ≤ 0.2 range fabricated by solid-state synthesis and usual sintering have been carried out. Distinct anomalies of dielectric and piezoelectric parameters, corresponding to the transition between rhombohedral (monoclinic) and tetragonal ferroelectric phases, have been observed in pure PFN and PFN-xPT compositions with PbTiO3 content up to 8 mol.%. The x,T-phase diagram of the PFN-xPT solid solution system has been constructed using these data.10. Yu.I. Yuzyuk, R.A. Shakhovoy, S.I. Raevskaya, I.P. Raevski, M. El Marssi and M.G. Karkut. Ferroelectric Q-phase in a NaNbO3 epitaxial thin film – Appl.Phys.Lett. 2010. V.96, №22. P.222904-1-222904-3 (IF= 3.787).ABSTRACT: Epitaxial NaNbO3 thin films have been grown by pulsed laser deposition on cubic (00l) MgOsubstrate with epitaxial La0.5Sr0.5CoO3 buffer layer. Micro-Raman spectroscopy studies revealed that the ferroelectric Q phase (Pmc21, Z=4) is stable in a 250-nm-thick film in contrast to the antiferroelectric phase P (Pbma, Z=8) known to exist in the bulk single crystals and ceramics of undoped stoichiometric NaNbO3. Temperature-dependent Raman spectra indicate that the Q phase is stable over a wide temperature range (at least from 80 to 600 K), while the low-temperature ferroelectric rhombohedral phase N, typical for NaNbO3 single crystals, is not observed.11. V.V. Laguta, J. Rosa, L. Jastrabik, R. Blinc, P. Cevc, B. Zalar, M. Remskar, S.I. Raevskaya, and I.P. Raevski. 93Nb NMR and Fe3+ EPR study of local magnetic properties of disordered magnetoelectric PbFe1/2Nb1/2O3 // Materials Research Bulletin. 2010.v.45, No.11. P.1720-1727. (IF= 2.108).ABSTRACT: The 93Nb NMR and Fe3+ EPR spectra of a magnetoelectric PbFe1/2Nb1/2O3 (PFN) single crystal as well as of PFN ceramics and nanopowder have been measured. The relation between the chemical disorder and the local magnetic structure has been determined. The data show the occurrence of an antiferromagnetic (AFM) phase transition at 145 and 135 K in both single crystal and ceramic samples, respectively. The AFM phase transition is however essentially smeared out in the nanopowder. Two different Nb sites exist which have different local magnetic fields which are essentialy distributed in value. These two Nb sites correspond to different types of ‘‘chemical’’ order: Fe rich, Nb poor and Fe poor, Nb rich regions. The temperature dependences of the sublattice magnetizations and the values of the superhyperfine fields at the Nb ions are obtained. NMR data suggest that a spin–glass like state of PFN below T = 20 K arises from the Fe poor, Nb rich regions.

12. M. El Marssi, Y. Gagou, J. Belhadi, F. De Guerville, Yu. I. Yuzyuk I. P. Raevski. Ferroelectric BaTiO3/BaZrO3superlattices : x-ray diffraction, Raman spectroscopy and polarization hysteresis loops //J. Appl.Phys. 2010. v. 108, 084104. 1-6. (IF= 2.169).ABSTRACT: Artificial superlattices (SLs) consisting of ferroelectric BaTiO3 (BT) and paraelectric BaZrO3

(BZ)have been growth by a pulsed laser deposition technique.. The out-of-plane lattice parameters of the SLs constituents were determined by modeling of the x-ray diffractograms. The results indicate that the polar c-axis of the BT layers lies in the plane of the substrate and BZ layers exhibit enhanced tetragonal distortion which is induced by the mismatch between the alternating BZ and BT layers. The Raman spectra give evidence of coupling between the constituent layers and a narrowing of the Raman peaks is attributed to a reduction in the disorder of the Ti4+ ions due to the epitaxial strain. 13. E. Dul'kin, E. Mojaev, M. Roth, I. P. Raevski, and S. A. Prosandeev. Nature of thermally stimulated acoustic emission from PbMg1/3Nb2/3O3–PbTiO3 solid solutions // Appl. Phys. Lett. 2009. V.94. P. 252904-1- 252904-3. (IF= 3.787).ABSTRACT: We discuss the nature of the thermally stimulated acoustic emission (AE) in single crystals ofPb(Mg1/3Nb2/3)O3–PbTiO3 (PMN-PT). In particular, we derive an expression describing the efficiency of AE and we discuss in this connection AE from pure PMN.We have carried out original experiments revealing the dependence of AE in PMN-PT on the electric bias fields, and we found that the AE efficiency of PMN-PT can be heavily enhanced in a certain temperature interval by applying an electric bias field.14. I. P. Raevski, S. P. Kubrin, S. I. Raevskaya, V. V. Titov, D. A. Sarychev, M. A. Malitskaya, I. N. Zakharchenko, and S. A. Prosandeev. Experimental evidence of the crucial role of nonmagnetic Pb cations in the enhancement of the Néel temperature in perovskite Pb1−xBaxFe1/2Nb1/2O3 // Phys. Rev. B 2009. V.80, № 2. P.024108-1 -024108-6. (IF= 3.69).ABSTRACT: Our experimental study of Pb1−xBaxFe1/2Nb1/2O3 shows that, the Néel temperature in this solid solution drops down at x=0.15/ 0.20, and, at the same threshold, the polarization also looses its long-range order. Thus, the multifunctional solid solution studied demonstrates a possibility of simultaneous controlling the magneticand ferroelectric properties by changing the concentration of only lead, which is a nonmagnetic ion.15. S. I. Raevskaya, I. P. Raevski, S. P. Kubrin, M. S. Panchelyuga, V. G. Smotrakov, V. V. Eremkin, S. A. Prosandeev. Quantum paraelectricity coexisting with a ferroelectric metastable state in single crystals of NaNbO3: a new quantum effect //J. Phys. Condens. Matter. 2008. V.20, №23.- P.232202. 1-5. (IF= 2.332).ABSTRACT: We experimentally show that, in contrast to the data having been collected so far, some single crystals of NaNbO3 exhibit a dielectric permittivity of several thousand, at low T , and this value is saturated when approaching 0 K on cooling. Other sodium niobate crystals (having larger dielectric losses) present a first-order phase transition to a ferroelectric phase on cooling (at 80–200 K). The dielectric permittivity at the phase transition obtained on cooling shows a tendency to increase and saturate, when the thermal hysteresis increases. We identify the ground state of the sodium niobate crystal exhibiting the smallest dielectric losses (in the studied set of crystals) as a novel quantum paraelectric state coexisting with a metastable ferroelectric state. In principle, the crystal presenting the state of quantum paraelectricity can be considered as having the largest (among the crystals studied)thermal hysteresis, for which the low boundary is below 0 K.16. S. I. Raevskaya, Yu. N. Zakharov, A. G. Lutokhin, A. S.Emelyanov, I. P. Raevski, M. S. Panchelyuga, V. V. Titov, and S. A. Prosandeev. Critical nature of the giant field-induced pyroelectric response in Pb(Mg1/3Nb2/3)O3–xPbTiO3 single crystals // Appl. Phys. Lett. 2008. V.93. № 4.- P. 042903.1-3. (IF= 3.787).ABSTRACT: We study the E-T phase diagram and dynamical pyroelectric coefficient of an (001)-oriented flux-grown 0.8 Pb(Mg1/3Nb2/3)O3–0.2PbTiO3 single crystal. We found that the highest pyroelectric coefficient can be achieved at the point having quasicritical features. These data establish a quasicritical behavior of the field-induced pyroelectric coefficients in relaxors.

17. S. Prosandeev. M. Panchelyuga, S. Raevskaya, I. Raevski, Theory of the dielectric nonlinearity in ferroelectric relaxors in the vicinity of the Vogel-Fulcher temperature under dc bias fields // Appl. Phys. Lett. 2007. V.91. № 24.- P. 242904.1-3.(IF= 3.787).ABSTRACT: Usually, dipole glass phase transitions are associated with the divergence of the third harmonic ofthe dielectric response. We show that, in reality, (i) random fields diffuse this singularity; (ii)even if the random field is absent, the divergence is one sided (it exists only at the temperatures, which are lower than the Vogel-Fulcher temperature); (iii) in the latter case, the divergence is followed by a jump of the first and third harmonics; and (iv) if the bias field exceeds the random field, all dielectric anomalies must be seen well.18. S. I. Raevskaya, A. S. Emelyanov, F. I. Savenko, M. S. Panchelyuga, I. P. Raevski, S. A. Prosandeev, Eugene V. Colla, Haydn Chen, S. G. Lu, R. Blinc, Z. Kutnjak, P. Gemeiner, B. Dkhil, L. S. Kamzina. Quasivertical line in the phase diagram of single crystals of PbMg1/3Nb2/3O3−(x)PbTiO3 (x=0.00, 0.06, 0.13 and 0.24) with a giant piezoelectric effect //Phys.Rev.B. 2007. V.76. 060101. 1-4. (IF= 3.69).ABSTRACT: We show that the phase diagram of the (001) Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-xPT) (x=0.00, 0.06, 0.13, and 0.24) and (111) PMN-0.24PT lead-magnesium niobate mixed with lead titanate possesses a quasiverticalline in the E electric field – T temperature plot, which hardly depends on the field. The existence of this linehas been confirmed by independent studies of single crystals grown in different laboratories, by measuring thedielectric permittivity, compliances, and optical transmission, also in different laboratories. A thermal hysteresisinherent to first order phase transitions complicates the phase diagram. The piezoelectric coefficients of the(001) PMN-xPT (x =0.06 and 0.13) have two peaks versus temperature, at finite fields. The first peak is dueto the quasivertical phase boundary. The second is in the vicinity of a turning point of the Tm(E) temperatureof the dielectric permittivity diffuse maximum. We show that the second peak prevails at reasonable fields, andthe piezoelectric coefficients have comparatively large values at this peak, even at small x.19. A.S. Emelyanov, S.I. Raevskaya, F.I. Savenko, V.Yu. Topolov, I.P. Raevski, A.V. Turik, A.L. Kholkin. Dielectric and piezoelectric properties of (001)-oriented (1 − x)Pb(Mg1/3Nb2/3)O3 –xPbTiO3 single crystals with 0.1≤ x ≤ 0.4 // Solid State Commun. 2007.-V.143, №3.- P.188–192. (IF= 1.839).ABSTRACT: Temperature and compositional dependences of the piezoelectric coefficient d33 and dielectric permittivity for (001)-oriented (1 − x) Pb(Mg1/3Nb2/3)O3-xPbTiO3 flux-grown single crystals have been studied in the wide compositional range (0.10 < x < 0.40). The effect of multiple configurations of the 71 (109) domains existing in the ferroelectric 3m phase on the apparent values of d33 and ε33 for composition x = 0.33 close to the morphotropic phase boundary is considered. The results obtained enable one to better define the compositional dependence d33(x) and to interpret inconsistencies in d33 values reported in the literature.20. A.A. Bogomolov , A.V. Solnyshkin, D.A. Kiselev, I.P. Raevsky, N.P. Protzenko, D.N. Sandjiev. Nonstationary photocurrent and pyroelectric response in aged Sn2P2S6 films //J. Europ. Ceram. Soc. 2007. V.27. № 13-15.-P. 3835–3838. (IF= 2.351).ABSTRACT: The photoelectric and pyroelectric properties of Sn2P2S6 films were studied by a dynamic method under excitation by periodic rectangular laser beam pulses (λ = 6328 A° ). In this case, an appearance of the nonstationary photoelectric response in the films under visible light irradiation (extrinsic excitation) was observed. It was found that temperature dependence of the unsteady current is connected to features of spontaneous polarizationbehaviour in Sn2P2S6 thin films. A nature of the nonstationary photoelectric response existence due to an electric field of the potential barrier near an interface is discussed.

21. F. De Guerville, M. El Marssi, I. P. Raevski, M.G. Karkut, Yu. I. Yuzyuk Soft mode dynamics and the reduction of Ti4+ disorder in Pb-free ferroelectric/relaxor superlattices BaTiO3/BaTi0.68Zr0.32O3 // Phys. Rev. 2006. V. B74. № 7. P.064107-1 - 064107-5. (IF= 3.69).ABSTRACT: We used pulsed laser deposition to grow a series of BaTiO3/2 / BaTi0.68Zr0.32O3/2 (BTZ/BT) superlattices (SL’s) with a modulation period that varies between 16 Å-1008 Å; the total thickness is kept constant at about 4000 Å. We determine the out-of-plane lattice parameters of the SL constituents by modeling the x-ray diffractograms of the SL’s. The results indicate that the polar c axis of the BT layers lies in the plane of the film. The Raman data reinforces this interpretation.22. Raevski I. P., Prosandeev S. A., Emelyanov A. S., Raevskaya S.I., Colla E. V., Viehland D., Kleemann W., Vakhrushev S. B., Dellis J-L., El Marssi M., Jastrabik L. Bias field effect on the temperature anomalies of dielectric permittivity in PbMg1/3Nb2/3O3- PbTiO3 single crystals //Phys. Rev. 2005. V. B72. № 18. P.184104-1 - 184104-8. (IF= 3.69).ABSTRACT: In contrast to ordinary ferroelectrics where the temperature Tm of the permittivity maximum monotonically increases with bias field E in (1 − x) Pb(Mg1/3Nb2/3)O3-xPbTiO3 (0<x<0.35)single crystals, Tm was found to remain constant or to decrease with E up to a certain threshold field Et, above which Tm starts increasing. The threshold field Etdecreases with increasing x, tending toward zero at approximately x=0.4. We explain thisdependence in the framework of models which take into account quenched random fields and random bonds.For crystals with 0.06<x<0.13, the E-T phase diagrams are constructed. 23. Prosandeev S. A., Raevski I. P. , Emelyanov A. S., Colla E. V., Dellis J-L., El Marssi M., Kapphan S. Е., Jastrabik L.. Nontrivial dependence of dielectric stiffness on bias field in relaxors and dipole glasses // J.Appl.Phys. 2005.V.98, № 1. P.014103.1 -6. (IF= 2.169).ABSTRACT: Dielectric permittivity studies in the field-cooled mode show a linear dependence of dielectricstiffness (inverse dielectric permittivity) on the dc bias in (1-x) Pb(Mg1/3Nb2/3)O3-xPbTiO3 crystals. We explain this unusual result in the framework of a theory of transverse, hydrodynamic-type instability of local polarization.24. Yuzyuk Yu. I., Simon P., Gagarina E., Hennet L., Thiaudière D., Torgashev V.I., Raevskaya S.I., Raevskii I.P., Reznitchenko L.A., Sauvajol J. L. Modulated phases in NaNbO3: Raman scattering, synchrotron x-ray diffraction, and dielectric investigations // J.Phys: Condens. Matter. 2005. V.17. № 33. P.4977-4990. (IF= 2.018).ABSTRACT: Raman spectra of sodium niobate (NaNbO3) were obtained in all phases and revealed a significant disorder in the high-temperatureU, T2 and T1 phases and a complicated folding of the Brillouin zone at the transitions into modulated S, R, P and N phases associated with the competitive zone-boundary soft modes (in-phase and out-of phase octahedral tilts) along the M–T–R line. An extensive Raman study combined with x-ray diffraction (XRD) and dielectric measurements confirmed the presence of the incommensurate (INC) phase in sodium niobate.25. Prosandeev S. A., Raevski I. P., Bunin M. A. Comment on “Conduction states in oxide perovskites: three manifestations of Ti3+Jahn-Teller polarons in barium titanate” // Phys.Rev.B. 2004. V.70. № 15. 157101-1- 157101-2. (IF= 3.69).ABSTRACT: In this comment to S. Lenjer, O. F. Schirmer, H. Hesse, and Th. W. Kool, Phys. Rev. B 66, 165106 (2002), we discuss the electronic structure of oxygen vacancies in perovskites. First-principles computations are infavor of rather deep levels in these vacancies, and Lenjer et al. even suggest that the electrons’ interaction energy is negative. However, data on electroconductivity are against both these scenarios.26. Raevski I. P., Raevskaya S.I., Prosandeev S. A., Shuvaeva V.A., Glazer A.M., Prosandeeva M. S., Diffuse first-order phase transition in NaNbO3:Gd // J.Phys: Condens. Matter . 2004. V.16, №15. P.L221-L226. (IF= 2.018).ABSTRACT: Dielectric permittivitymeasurements showthat (1−x)NaNbO3–(x)Gd1/3NbO3 crystals, at x = 0.09, exhibit a first-order phase transition near 150 ◦C that is diffuse over a wide temperature interval. The area of the ε(T)

thermal hysteresis loop was found to depend both on annealing and cooling temperatures. Optical studies in polarized light show a decrease of the domain sizes at this phase transition. The results obtained are fitted assuming a spatial distribution of Curie temperatures.27. Raevski I.P., Reznitchenko L.A., Malitskaya M.A., Shilkina L.A., Lisitsina S.O., Raevskaya S.I., Kuznetsova E.M. NaNbO3 –based relaxor // Ferroelectrics .-2004.- V.299, №1-4.-P.95-101. (IF= 0.447).ABSTRACT: Binary NaNbO3-ABO3 perovskite solid solutions belonging to the group II according to N.N. Krainik classification (Izv.Akad. Nauk SSSR, Ser. Phys. 28, 643 (1964)) exhibit a relaxor-type behavior when the second component concentration exceeds a threshold value x0, corresponding to the abrupt decrease of the dielectric permittivity ε maximum temperature Tm. The Tm values of all the known binary NaNbO3-ABO3 relaxorcompositions are well below the room temperature and the maximal ε values εm are much lower than in the case of Pb-containing relaxors. However both Tm and εm values may be increased substantially by Li or K-doping leading to the formation of ternary NaNbO3-ABO3-LiNbO3 (KNbO3) solid solutions.28. Bokov A.A., BingY.-H., Chen W., Ye Z.-G., Bogatina S. A., Raevski I. P., Raevskaya S. I., Sahkar E.V. Empirical scaling of the dielectric permittivity peak in relaxor ferroelectrics //Phys.Rev.B. 2003. V.68. № 5. 052102. 1-4. (IF= 3.69).ABSTRACT: Dielectric permittivity ε as a function of temperature is measured in PbMg1/3Nb2/3O3 and a number of other relaxor ferroelectrics with the perovskite structure. It is found that the data taken from the high-temperatureslopes of the diffused permittivity peaks of all the materials studied can be collapsed onto a single scaling line. This formula describes the static conventional relaxor susceptibility, which provides the dominant contribution to the permittivity peak at temperatures above the temperature of the maximum. In the close vicinity of the peak temperature and below, the scaling is disturbed due to the conventional relaxor dispersion.29. Raevski I.P. , Prosandeev S.A. , Bogatin A.S. , Malitskaya M.A., Jastrabik L. High Dielectric Permittivity in AFe1/2B1/2O3 Nonferroelectric Perovskite Ceramics (A - Ba, Sr, Ca; B - Nb, Ta, Sb) //J.Appl.Phys. 2003. V.93, № 7. P.4130-4136. (IF= 2.169).ABSTRACT: AFe1/2Nb1/2O3 (A-Ba, Sr, Ca; B-Nb, Ta, Sb) ceramics were synthesized and temperature dependences of dielectric permittivity were measured at different frequencies. The experimental data obtained show very high values of dielectric permittivity in a wide temperature interval that is inherent to so-called high-k materials. Analyses of these data establish a Maxwell–Wagner mechanism as a main source for the phenomenon observed.30. Shuvaeva V. A., Pirog I., Azuma Y., Yagi K., Sakaue K., Terauchi H., Raevski I.P., Zhuchkov K., Antipin M.Yu. The local structure of mixed-ion perovskites // J.Phys.: Condens. Matter. 2003. V.15. P.2413-2421. (IF= 2.018).ABSTRACT: The temperature-dependent Nb K-edge absorption spectra of several mixed ion Pb-containing perovskite compounds were analysed to determine the Nb displacement and to trace its changes through the phase transitions. Both extended x-ray absorption fine structure (EXAFS) and the pre-edge region of the spectra were involved in the analysis. The results show that, in the compounds studied, Nb occupies an off-centre position with symmetry lower than that implied by macroscopic symmetry.31. Raevski I.P., Prosandeev S.A. A new, lead free, family of perovskites with a diffuse phase transition: NaNbO3 – based solid solutions //J.Phys.Chem.Solids. 2002. V.63, №10, p.1939-1950. (IF= 1.417).ABSTRACT: NaNbO3-xABO3 perovskite solid solutions belonging to the group II according to N.N. Krainik classification (Izv.Akad. Nauk SSSR, Ser. Phys. 28, 643 (1964)) exhibit an abrupt diffusion of the dielectric permittivity ε maximum and relaxor-type behavior when the second component concentration exceeds a threshold value x0. The concentration phase transition to this relaxor-like phase is abrupt (of the first order kind)that is seen from the step on the dependence of the dielectric permittivity ε maximum temperature Tm on x. Some relaxor-like properties appeareven at x<x0 in the course of cooling while disappear during the course of heating. Due to this fact and because of coupling of the antiferoelectric (AFE) and feroelectric (FE) order parameters a giant ( up to 100 K) temperature hysteresis of ε(T) arises at AFE-FE first order phase transition.

Vitaliy TOPOLOV (h= 14) 1. Topolov V.Yu., Bowen C.R. Electromechanical properties in composites based on ferroelectrics. – London: Springer, 2009.– 202 p.ABSTRACT: The book discusses the latest theoretical and experimental results on the effective electromechanical (piezoelectric, dielectric and elastic) properties in piezo-composites based on ferroelectrics. For the last decades, single-crystal, bulk ceramic and thin-film ferroelectrics have found a number of various applications as a result of their remarkable piezoelectric properties. Recent work in the field of smart materials demonstrates that both ferroelectricity and piezoelectricity represent an important link between solid state science and engineering. The book investigates the problem of prediction and non-monotonicity of the effective electromechanical properties in different two- and three-component composites based on ferroelectric ceramics and relaxor-ferroelectric single crystals. Central to the book is the analysis of interrelations between the electromechanical constants of the components, and the description of different analytical schemes for averaging the properties of these materials with different connectivity and microgeometrical characteristics. The book not only highlights the advantages of different methods for predicting the electromechanical properties and choosing the optimum components, but also demonstrates the non-trivial behavior of specific composite architectures and their parameters which are valuable for transducer, sensor, actuator, hydroacoustic, and other applications.2. Topolov V. Yu. Heterogeneous Ferroelectric Solid Solutions. Phases and Domain States.– Berlin, Heidelberg: Springer, 2011.– 156 p.ABSTRACT: First book on phases and domain states in ferroelectric solid solutions Delivers a basic treatment in connection with practical applications. The book deals with perovskite-type ferroelectric solid solutions for modern materials science and applications, solving problems of complicated heterophase/domain structures near the morphotropic phase boundary and applications to various systems with morphotropic phases. In this book domain state–interface diagrams are presented for the interpretation of heterophase states in perovskite-type ferroelectric solid solutions. It allows to describe the stress relief in the presence of polydomain phases, the behavior of unit-cell parameters of coexisting phases and the effect of external electric fields. The novelty of the book consists in (i) the first systematization of data about heterophase states and their evolution in ferroelectric solid solutions (ii) the general interpretation of heterophase and domain structures at changing temperature, composition or electric field (iii) the complete analysis of interconnection domain structures, unit-cell parameters changes, heterophase structures and stress relief.3. Topolov V.Yu., Bowen C.R., Glushanin S.V. (2010): High performance of advanced composites based on relaxor-ferroelectric single crystals. In: Piezoceramic Materials and Devices, Ed. I.A. Parinov (Hauppauge: Nova Science Publishers), p.71-112. ISBN 978-1-60876-459-4.BOOK DESCRIPTION: Piezoelectric materials and composites and also the devices based on them have found wide applications in the modern technologies. This new book drives the reader from the concepts and ideas in this scientific area to theoretical, model and experimental results obtained some internationally recognized research teams. It is a collection of seven comprehensive overview papers prepared by leading scientists in Russia in order to collect the involved expertise in the area of novel piezoelectric materials, composites and devices and also methods of their investigation.4. Topolov V.Yu., Krivoruchko A.V. (2010): Ferroelectric PbTiO3: From a single-domain state to composite components. In: Perovskites: Structure, Properties and Uses, Ed. M. Borowski (Hauppauge: Nova Science Publishers), p.481-499. ISBN 978-1-61668-525-6. BOOK DESCRIPTION: Perovskite is a calcium titanium oxide mineral species composed of calcium titanate. This new book discusses perovskite thin films, which are widely employed in today's advanced technology. The broad range of physical properties in such category of materials has offered various functionalities in devices ranging from dynamic random access memories and ferroelectric nonvolatile memories to piezoelectric and optical devices. The structural, magnetic and electron transport properties of ordered-disordered perskovite cobaltites is discussed as is perovskite-type oxides, ferroelectric PbTiO3 from a single-domain state to composite components.

5. Topolov V.Yu., Krivoruchko A.V., Bisegna P., Glushanin S.V. (2011): Orientation effects in novel composites based on relaxor-ferroelectric single crystals. In: Ferroelectrics and Superconductors: Properties and Applications, Ed. I.A. Parinov (New York: Nova Science Publishers), p.45-80. ISBN 978-1-61324-518-7.BOOK DESCRIPTION: This book touches upon theoretical and experimental studies of superconductive materials and their applications. The chapters have been prepared by internationally recognized teams from Russia, Austria, Italy and Taiwan in the field of theoretical, model and experimental methods and investigations of different ferroelectric and superconductive materials, composites and novel devices designed on their base. The book also addresses students, post-graduate students, scientists and engineers, taking part in the development and research of erroelectric, superconductive and related materials.6. Topolov V.Yu., Bisegna P. (2012): Piezoelectric anisotropy in modern composites based on ferroelectrics. In: Anisotropy Research: New Developments, Ed. H. Lemu (New York: Nova Science Publishers), p.25-44. ISBN 978-1-62081-977-7.BOOK DESCRIPTION: Anisotropy is a term used to indicate the directional dependence of a biological, chemical, geometrical, mechanical or physical property of a system that develops in different ways along different spatial axes. This material behavior is observed in many engineering disciplines, computer graphics, geology and geophysics, medicine, neurosciences and natural sciences. Thus the research approaches within those disciplines accordingly varies. This book has collected contributions of new research developments and the corresponding research results from different disciplines with particular focus on experimental, numerical and theoretical studies of material property variations. Thus, the materials in this book indicate significant directions on new research progresses and are expected to give future research perspectives in anisotropy behavior.7. Topolov V.Yu., Bowen C.R. Electromechanical properties in composites based on ferroelectrics. – London: Springer, 2009.– 202 p.8. Topolov V. Yu. Heterogeneous Ferroelectric Solid Solutions. Phases and Domain States.– Berlin, Heidelberg: Springer, 2011.– 156 p.9. Bondarenko, E.I., Topolov, V.Yu. and Turik, A.V. (1990): The effect of 90° domain wall displacements on piezoelectric and dielectric constants of perovskite ferroelectric ceramics. Ferroelectrics 110, 53-56 (IF = 0.391).10. Bondarenko, E.I., Topolov, V.Yu. and Turik, A.V. (1991): The role of 90° domain-wall displacements in forming physical properties of perovskite ferroelectric ceramics. Ferroelectrics. Letters Section 13, 13-19 (IF = 0.931).ABSTRACT: A proposed model which takes into account an elastic interaction between a polydomain grain and a surrounding ceramic matrix under weak external mechanical stresses has been used for evaluating a contribution from 90° domain wall displacements to piezoelectric and elastic constants of the perovskite ferroelectric ceramics. A difference between experimental and averaged constants of BaTiO3 ceramics can be explained by the estimated contribution.11. Balyunis, L.E., Topolov, V.Yu., Bah, I.S., and Turik, A.V. (1993): The S-type domain and twin boundaries in plate-like PbZrO3 crystals having complicated twinned structures. Journal of Physics: Condensed Matter 5, 1419-1426 (IF = 2.546).Abstract. Four kinds of S-type domain and twin boundaries in the ferroelectric R3m and antiferroelectric Pbam phases of plate-like PbZrO3 crystals with complicated twinned structures have been described. Conditions for thermal stability of S-boundary orientations in perovskites have been formulated.12. Topolov, V.Yu. and Turik, A.V. (1995): Crystallographic aspects of interfaces in ferroelectrics. Defect and Diffusion Forum, Pt.A 123-124, 31-50 (H Index: 20).Abstract. This paper contains a review of works devoted to crystallographic investigations of domain and phase boundaries in ferroelectrics.13. Turik, A.V. and Topolov, V.Yu. (1997): Ferroelectric ceramics with a large piezoelectric anisotropy. Journal of Physics D: Applied Physics 30, 1541-1549 (IF = 2.544).ABSTRACT: This review concerns the experimental and theoretical publications devoted to the important problem of the large piezoelectric anisotropy in -based polarized ferroelectric ceramics.

14. Topolov, V.Yu. and Turik, A.V.(1999): Nonmonotonic concentration dependence of piezoelectric coefficients of 1-3 composites. Journal of Applied Physics 85, 372-379 (IF = 2.168).ABSTRACT: Reported are results of studying nonmonotonic concentration dependences of piezoelectric coefficients e3j

∗, d3j∗ and their anisotropy ζe and ζd, respectively, which pertain to the 1–3 composite.

Changing the piezoelectric properties of the composite is plotted by variations of ratios between elastic and piezoelectric constants of components and for various volume fractions of one of the components. Systems of conditions providing extreme points of the e3j

∗ and d3j∗ functions and discontinuity points of the ζe and ζd

functions are formulated. The role of electromechanical constants of the components and some connections between these constants in reaching the nonmonotonicity are discussed15. Levassort, F., Topolov, V.Yu. and Lethiecq, M. (2000): A comparative study of different methods of evaluating effective electromechanical properties of 0–3 and 1–3 ceramic / polymer composites. Journal of Physics D: Applied Physics, 33, 2064-2068 (IF = 2.544).ABSTRACT: The results of the evaluation of different effective parameters of 0-3 and 1-3 piezoactive composites are reported. For this, a matrix method previously developed for 2-2 connectivity is used and its application extended to 1-3 and 0-3 connectivities. Simulations are made with three perovskite-type ferroelectric ceramics and a vinylidene fluoride/trifluoroethylene piezoelectric polymer. Comparisons are shown and discussed between the different compositions, connectivities and other models and calculation methods. Particular attention is focused on factors leading to the appearance of extreme, discontinuity points and other features of effective parameters which are functions of volume concentrations of components (phases).16. Topolov, V.Yu. and Turik, A.V. (2001): A new monoclinic phase and features of stress relief in PbZr1-xTixO3 solid solutions. Journal of Physics: Condensed Matter 13, L771-L775 (IF = 2.546).ABSTRACT: We analyse the possibilities of elastic matching and effective internal stress relief at the coexistence of polar phases in ferroelectric PbZr1-xTixO3 compositions close to the morphotropic phase boundary. The important role of the polydomain (twinned) monoclinic phase in this stress relief over wide concentration and temperature ranges is discussed. A new link between phase boundaries in the phase diagram, reported by Noheda et al (Noheda B, Cox D E, Shirane G, Guo R, Jones B and Cross L E 2001 Phys. Rev. B 63 014103), and optimal domain volume concentrations, calculated in the present work, is revealed.17. Topolov, V.Yu. and Glushanin, S.V. (2002): Evolution of connectivity patterns and links between interfaces and piezoelectric properties of two-component composites. Journal of Physics D: Applied Physics 35, 2008-2014 (IF = 2.544).ABSTRACT: We report the results of studying the evolution of α-β connectivity patterns and the role of systems of interfaces inherent in two-component piezoactive composites. A scheme demonstrating links between so-called `junction' 2-2, 1-1, 1-3, and 3-1 connectivity patterns, and all the rest α-β connectivity patterns (α,β = 0,1,2, and 3) is first put forward. Important features of the evolution of the connectivity patterns and versions of the formation of the α-β ceramic/polymer composite structures are discussed. On the basis of the approach developed in this paper the 1-2 ceramic/polymer composite (point symmetry group mm2) and some peculiarities of its piezoelectric properties are first analysed. Physical and microstructural reasons for an original competition between effective piezoelectric coefficients d31* and d32* or e31* and e32*, as well as reasons for max e33* of the 1-2 composite are considered in connection with concentration behaviour of piezoelectric properties of the 1-1 and 1-3 composites.18. Topolov, V.Yu. and Turik, A.V. (2002): Intermediate monoclinic phase and electromechanical interactions in xPbTiO3 – (1 – x)Pb(Zn1/3Nb2/3)O3 single crystals. Physics of the Solid State 44, 1355-1362 (IF = 0.711).ABSTRACT: The elastic matching of phases in the vicinity of the morphotropic phase boundary in xPbTiO(3)-(1 - x)Pb(Zn1/3Nb2/3)O-3 crystals is investigated in an external electric field with strength E parallel to [001]. The field dependences of the unit cell parameters of the monoclinic phase are determined experimentally in the range 0 less than or equal to E less than or equal to 2 MV/m. The results obtained are used in analyzing specific features in the electromechanical properties of xPbTiO(3)-(1 - x)Pb(Zn1/3Nb2/3)O-3 crystals (0.08 less than or similar to x less than or similar to 0.09), in which the monoclinic phase is intermediate between the rhombohedral and tetragonal phases and can coexist with

these phases. A correlation between the optimum volume concentrations of domains or twins in different two-phases states is revealed and interpreted for the first time.19. Topolov, V.Yu. (2002): Intermediate monoclinic phase and elastic matching in perovskite-type solid solutions. Physical Review B65, 094207 – 6 p. (IF = 3.691).ABSTRACT: This paper is devoted to the study of elastic matching of phases coexisting in systems of perovskite-type solid solutions close to morphotropic phase boundaries. Determined are different interfaces that separate single-domain or polydomain phases in (1-x)PbZn1/3Nb2/3O3-xPbTiO3 single crystals and PbZr1-xTixO3 ceramic grains. These interfaces are parallel to so-called zero net strain planes. Some results of recent experimental studies of the crystal structure and electromechanical properties are analyzed in connection with the revealed simplification of the domain structure in the intermediate monoclinic phase of (1-x)PbZn1/3 Nb2/3O3-xPbTiO3 single crystals. The important role of the monoclinic phase in relieving stress at the phase coexistence in both the systems is considered. Links between optimal domain volume concentrations derived from unit-cell parameters' behavior are discussed on the basis of concepts of the polarization rotation path proposed by Fu and Cohen.20. Bowen, C.R. and Topolov, V.Yu. (2003): Piezoelectric sensitivity of PbTiO3-based ceramic / polymer composites with 0–3 and 3–3 connectivity. Acta Materialia 51, 4965-4976 (IF = 3.755).ABSTRACT: This paper describes the modelling and comparison of piezoactive composites of 0-3 and 3-3 geometry. Algorithms for the evaluation of effective elastic, piezoelectric and dielectric constants are proposed which can be used for the prediction of piezoelectric sensitivity and optimisation of properties. The hydrostatic piezoelectric voltage coefficient g(h), figure of merit d(33).g(33) and hydrostatic figure of merit d(h).g(h), are calculated for PbTiO3 based piezocomposites in which the anisotropy factor -d(33)/d(31) of the piezoelectric phase can be varied from small to infinitely large values. Maxima of these parameters are determined and factors influencing piezoelectric sensitivity of the composites are analysed.21. Topolov, V.Yu. and Ye, Z.-G. (2004): Coexistence of morphotropic phases in (1 – x)Pb(Mg1/3Nb2/3)O3 – PbTiO3 solid solutions. Physical Review B 70, 094113 – 8 p. (IF = 3.691).ABSTRACT: We report the results of crystallographic analysis of various complex heterophase states that occur around the morphotropic phase boundary in the relaxor-based (1-x)Pb(Mg1/3Nb2/3)O-3-xPbTiO(3) solid solutions at room temperature. Different variants of the coexistence of two or three morphotropic phases are analyzed based on the structural data of Noheda [Phys. Rev. B 66, 054104 (2002)] and Singh and Pandey [Phys. Rev. B 67, 064102 (2003)], and interpreted by taking into account the features of elastic matching of polydomain (twinned) regions. A model of interpenetrating phases is proposed to describe the two-phase states on the condition of a complete relieving of the mechanical stress at interfaces. A good agreement between the experimental and theoretical results on the variants of phase coexistence has been achieved.22. Bezus, S.V., Topolov, V.Yu. and Bowen, C.R. (2006): High-performance 1–3-type composites based on (1 – x) Pb(A1/3Nb2/3)TiO3 – x PbTiO3 single crystals (A = Mg, Nb). Journal of Physics D: Applied Physics 39, 1919-1925 (IF = 2.544).ABSTRACT: This paper describes the concentration dependences of piezoelectric coefficients, squared figures of merit and electromechanical coupling factors which have been calculated for 1-3 and 1-0-3 piezo-active composites based on single crystals of relaxor-ferroelectric solid solutions of (1 - x)Pb(A(1/3)Nb(2/3))O3-xPbTiO3 where A = Mg, Zn. The role of the single-crystal component, its electromechanical properties and the polymer matrix (monolithic or porous) in forming these concentration dependences is analysed to demonstrate the ranges in which effective composite parameters are most sensitive to material properties and composite architecture, with particular emphasis on where their maximum values are attained. The basic variables in this study are the chemical composition (x and A), volume concentrations of the single-crystal component, the presence of pores in the polymer matrix and the aspect ratio of the spheroidal pores. It has been shown that particularly high values of piezoelectric coefficient g(33)* similar to 10(2) mV m N-1 and hydrostatic piezoelectric coefficients g(h)* similar to 10(2) mV mN(-1) and d(h)* similar to (10(2)-10(3)) pC N-1 are expected in the 1-0-3 0.67Pb(M1/3Nb2/3)O-3-0.33PbTiO(3) single crystal / porous araldite composite with spheroidal pores in the matrix.

Victoria SHUVAEVA (h=10)1. V.A.Shuvaeva, D.Zekria, A.M.Glazer, Q.Jiang, S.M.Weber, P.Bhattacharya, P.A.Thomas, The local structure of the lead-free relaxor ferroelectric (KxNa1-x)0.5Bi0.5TiO3, 2005, Phys. Rev. B, (2005) 71, 174114 (IF=3.69)ABSTRACT: The local environment of Bi and Ti atoms in the lead-free relaxor ferroelectric solid-solution (KxNa1-x)0.5Bi0.5TiO3 has been studied as a function of K concentration and as a function of temperature for the x=0 end-member by XAFS. It is found that the local environment of Bi is much more distorted than that determined from conventional diffraction experiments. The shortest Bi-O distances are determined to be 2.22 Å, and are 0.3 Å shorter than those calculated from the crystallographic data. Several possible models of the Bi coordination environment, which are consistent with the XAFS data and provide bond-valence sums for Bi that are closer to the theoretical values, are proposed. The Ti displacement from the centre of the oxygen octahedron increases with K concentration while the shortest Bi-O distance shows no compositional dependence. In K0.5Bi0.5TiO3 the value of the Ti displacement is determined to be 0.18 Å. The changes of the macroscopic symmetry at the phase transition points in Na0.5Bi0.5TiO3 do not lead to changes of the radial atomic distribution around Ti, which is well off-centre over the whole temperature range up to and including the paraelectric cubic phase. The results can be explained by assuming the presence of structural disorder.2. D. Zekria, V. A. Shuvaeva and A. M. Glazer Birefringence imaging measurements on the phase diagram of Pb(Mg1/3Nb2/3)O3-PbTiO3 J. Phys. Condens. Matter 17 (2005) 1593-1600. (IF=2.546)ABSTRACT: The phase diagram of Pb(Mg1/3Nb2/3)1-xTixO3(PMN–PT) has been determined to high accuracy over the whole compositional range using birefringence imaging. A steep change has been detected in the thermal hysteresis of phase transitions in the morphotropic phase boundary region at x = 0.295 at the boundary between relaxor and non-relaxor phases. At the same composition at a temperature about 30 ◦C below Tc a monoclinic phase appears. The phase transition between non-relaxor and the monoclinic phase is characterized by a pronounced thermal hysteresis and a large jump in birefringence, showing that this is of first order. A significant change in slope for the compositional dependence of Tc has been found for x =0.45, suggesting a boundary between the tetragonal phase and a phase of lower symmetry. The temperature dependence of the birefringence has been measured for a number of different compositions in the range 0.3 <x <1, in which it is found that the birefringence of the monoclinic phase is much higher than that seen in the other phases for x <0.5.3. V.A. Shuvaeva, A. M. Glazer and D. ZekriaThe macroscopic symmetry of Pb(Mg1/3Nb2/3)1-xTixO3 in the morphotropic phase boundary region (x = 0.25-0.45) J. Phys. Condens. Matter (2005) (IF=2.546) ABSTRACT: The macroscopic symmetry of Pb(Mg1/3Nb2/3)1-xTixO3 (PMN-PT) crystals with x = 0.27-0.45 has been studied by optical microscopy. Precise data on the temperature dependence of the birefringence and optical extinction directions have been obtained. Two different low-symmetry phases separating rhombohedral and tetragonal phases have been observed in the compositional range x = 0.3-0.45. The optical extinction in the range x = 0.3-0.37 is consistent with Cm space group symmetry, while for x = 0.37-0.45 Pm symmetry is appropriate. Gradual rotation of the optical indicatrix has been found at temperatures just below Tc in crystals with x = 0.27-0.3. A refined phase diagram is presented.4. S. A. Hayward, M. A. Carpenter, S. A. T. Redfern, E. K. H. Salje, F. D. Morrison, J. F. Scott, K. S. Knight, S. Tarantino, A. M. Glazer, V. Shuvaeva and P. Daniel. Transformation processes in LaAlO3: neutron diffraction, dielectric, thermal, optical and Raman studies, Phys. Rev. B, (2005)72, 054110.(IF=3.69)ABSTRACT: The behavior of the Pm3¯m-R3¯c phase transition in LaAlO3 _TC=813 K from differential scanning calorimetry measurements_ has been studied using temperature-dependent measurements of the crystal structure, dielectric relaxation, specific heat, birefringence, and the frequencies of the two soft modes via Raman spectroscopy. While all these experiments show behavior near TC consistent with a second-order Landau transition, there is extensive evidence for additional anomalous behavior below 730 K. Below this temperature, the two soft mode frequencies are not proportional to each other, the spontaneous strain is not proportional to the square of the AlO6 rotation angle, and anomalies are seen in the birefringence. Twin domains, which are mobile above 730 K, are frozen below 730 K. These anomalies are consistent with biquadratic coupling between the primary order parameter of the transition AlO6

rotation_ and a second process. From the dielectric results, which indicate a smooth but rapid increase in conductivity in the temperature range 500–800 K, we propose that this second process is hopping of intrinsic oxygen vacancies. These vacancies are essentially static below 730 K and dynamically disordered above 730 K. The interaction between static vacancies and the displacive phase transition is unfavorable. A similar anomaly may be observed in other aluminate perovskites undergoing the same transition.5. D. Zekria, A.M. Glazer, V. Shuvaeva, J. Dec, S. Miga, Birefringence of lead titanate (PbTiO3) Appl. Crystallography 2004, 37: 551-554 (IF=5.152)ABSTRACT: Since lead titanate was first grown in single-crystal form in the 1930s, several independent reports of its linear birefringence have been published. Whilst there is overall qualitative agreement on its behaviour with temperature, the absolute values show some degree of variation. At 298 K they range from 0.009 to 0.013, a relative spread of 40%, whilst at 673 K the discrepancy is even greater. This paper reports unexpected results obtained from independent measurements of a selection of crystals that have been grown recently, in which the birefringence is some four times greater than hitherto believed. This has important consequences for the use of birefringence measurement as a means of studying phase transitions in crystals. Intrinsic values of birefringence for lead titanate are measured for the first time.6. V.A.Shuvaeva, I.Pirog, Y.Azuma, K.Yagi, K.Sakaue, H.Terauchi, I.P.Raevskii, K.Zhuchkov, M.Yu.Antipin, The local structure of mixed-ion perovskites, Journal of Physics, Condensed Matter, 2003, 15 (14): 2413-2421 (IF=2.546)ABSTRACT: The temperature-dependent Nb K x-ray absorption of fine structure (XAFS) spectra of several mixed-ion Pb-containing perovskite compounds were analysed to determine the Nb displacement and to trace its changes through the phase transitions. Both extended XAFS (EXAFS) and the pre-edge region of the spectra were involved in the analysis. The results show that, in the compounds studied, Nb occupies an off-centre position with symmetry lower than that implied by macroscopic symmetry. The magnitude and direction of the Nb off-centre displacement do not display any noticeable temperature change and are not affected by the change inmacroscopic symmetry. TheNb–O distribution and its temperature evolution do not show any distinct dependence on the degree of compositional ordering and properties of the samples.7. V.A.Shuvaeva, Y. Azuma, K.Yagi, K.Sakaue, H.Terauchi, Polarized XAFS Study of high-temperature phases of NaNbO3, Journal of Synchrotron Radiation, 2001, V.8, p.833-835. (IF=2.726) ABSTRACT: Temperature dependence of the Nb displacement relative to the center of oxygen octahedron in NaNbO3 has been studied by polarized Nb K XAFS. Spectra were measured at two orientations of a single crystalline sample. Room temperature EXAFS data are in a good agreement with earlier X-ray diffraction data: Nb antiferroelectric displacements were found to be orthogonal to the b axis. Analysis of the temperature dependent EXAFS data didn’t reveal any abrupt changes of Nb-O distances in the phase transition points. In all high-temperature paraelectric phases Nb appeared to be displaced to the off-center positions. Displacements, orthogonal to b axis, remained almost constant, while displacement along b axis gradually increased with temperature, so that in the cubic phase the displacements along all axes became equal. This shows, that disorder plays an important role in the high temperature phases. The above results are supported also by the analysis of the pre-edge structure, - the integral intensity of the pre-edge peak was temperature-independent when the polarization vector of the X-rays was orthogonal to b axis and gradually increased with temperature when the polarization was parallel to b.8. A.T.Shuvaev, B.Yu.Helmer, T.A.Lyubeznova, V.A.Shuvaeva, Laboratory diffractometer-based XAFS spectrometer, Journal of Synchrotron Radiation, 1999, V.6, p.158-160. (IF=2.726)ABSTRACT: The device has been developed to allow XAFS spectra of good quality to be obtained using conventional powder diffractometer. The device is based on the mechanical system which synchronize the changes of curvature radius of bent crystal-monochromator with the Bragg angle. Due to high resolution (1-10 eV depending on the wavelength) and photon flux only several hours are needed to perform quality XAFS experiment. The device is easy to operate and can be successfully used both for XAFS investigations and for student’s practice.9. V.A. Shuvaeva, Y. Azuma, K. Yagi, H. Terauchi, R. Vedrinski, V. Komarov, H. Kasatani, Ti Off-Center Displacements in Ba1-xSrxTiO3 Studied by EXAFS, Physical Review, 2000, V.62, N5, p.2969-2972. (IF=3.69)

ABSTRACT: Local structure of Ba1-xSrxTiO3 with x=0.050 –0.75 has been studied using x-ray-absorption fine-structure spectra, measured at the Ba K edge at room temperature. The dependence of the mean-square relative displacements and the third cumulant of Ba-O and Ba-Ti distribution functions on the Sr concentration have been analyzed. The results show that Ba off-center displacement vanishes abruptly at x50.3, which is the boundary point between tetragonal and cubic phases, whereas Ti off-center displacement decreases gradually with Sr concentration and approaches zero at about x50.7. The change of macroscopic symmetry does not cause any significant change of Ti displacement. The results indicate that Ti atoms are disordered in a wide range of Sr10. V.A.Shuvaeva, K.Yanagi, K.Yagi, K.Sakaue, H.Terauchi, Polarized XAFS Study of the Atomic Displacements and Phase Transitions in KNbO3, Journal of Synchrotron Radiation, 1999, V.6, p.367-369. (IF=2.726)ABSTRACT: Polarized XAFS technique has been applied for the determination of the directions and the values of the Nb displacements relative to the centers of oxygen octahedra in KNbO3. The temperature dependence of the both EXAFS and XANES spectra were analyzed in order to reveal the role of disorder in the phase transitions of this compound. The polarized XAFS appeared to be enough sensitive to detect the delicate balance between order-disorder and displacive mechanisms of the phase transitions in KNbO3. The magnitude of the pre-edge peak on the Nb K-XAFS spectra was found to be highly correlated with the value of the Nb off-center displacement, obtained by fitting of the EXAFS spectra11. V.A.Shuvaeva, K.Yanagi, K.Yagi, K.Sakaue, H.Terauchi, The local structure and the nature of phase transitions in KNbO3, Solid State Communications, 1998, V.106, N6, pp.335-339. (IF=1.839)ABSTRACT: The direction and magnitude of Nb displacements from the center of oxygen octahedron in orthorhombic, tetragonal and cubic phases of KNbO3 were determined by means of polarized X-ray absorption fine structure (polarized XAFS). The XAFS spectra for Nb K-edge were obtained from plate-like single crystals in a transmission mode. It is found that in the orthorhombic phase the direction of the Nb displacement is very close to the ‘polar axis. However, the disorder of Nb positions grows gradually with increasing temperature. All phase transitions are governed by bothdisplacive and order-disorder mechanisms. The rhombohedral-to-orthorhombic phase transition is considered as essentially a displacive type, while the order-disorder component is dominant in the tetragonal-to-cubic phase transition.

Yuriy YUZYUK (h=15) ISI citation index 983 (updated 2012-12-19)1. Yuzyuk Yu.I., Dmitriev V.P., Rabkin L.M., Burmistrova L., Shuvalov L.A., Smutny F., Gregora I., Petzelt J. “The transition to a proton glass state in Cs5H3(SO4)4

.H2O”. Solid State Ionics 1995, v.77, p.122-127. Цит. 18. (IF 1.089)ABSTRACT: Raman scattering, calorimetric and dielectric spectroscopy data for Cs5H3(SO4)4 H2O single crystal taken at 20–300 K are recorded. The glass transition temperature Tg, as determined from DSC, shows a remarkable hysteresis: 261 K on heating and 248 K on cooling. The change in the molar capacity is 27J/mol K. The dielectric data (30 KHz- 2.2 MHz) show a pronounced dispersion whose relaxation frequency obeys Arrhenius law. An increase in the isotropic component of Rayleigh light scattering was observed below Tg. Raman scattering data indicate a conservation of hexagonal crystal symmetry in the glassy phase, and a lowering of the site symmetry. The transition from dynamic to static disorder is discussed. 2. Yuzyuk Yu.I., Dmitiriev V.P., Rabkin L.M., Smutny F., Gregora I., Dolbinina V.V., Shuvalov L.A. “Raman spectra of in Cs5H3(SO4)4

.H2O crystals in the proton glass state”. J. Phys.: Condens. Matter 1996, v.8, p.3965-3975. Цит. 13. (IF 1.562)ABSTRACT: Polarized Raman spectra of Cs5H3(SO4)4 H2O (PCHS) single crystals were measured in the frequency range 0–4000 cm−1 at 20–300 K, i.e. both below and above the glass transition temperature (Tg). The evolution of the spectra with decreasing temperature indicates that the orientational disorder of SO4 ions and H2O molecules changes at Tg from the dynamical to a static one. A scenario for the glass transition and a model of the resulting glass state is suggested, in which the water molecules (H bonds) play the role of binding constituents of the isolated sulphate complexes H3(SO4)4.

3. Uvarov N.F., Vanek P., Yuzyuk Yu.I., Zelezny V., Studnicka V., Bokhonov B.B., Dulepov V.E., Petzelt J. “Properties of rubuduim nitrate in ion-conducting RbNO3-Al2O3 nanocomposites”. Solid State Ionics 1996, v.90, p.201-207. Цит. 36 (IF 1.089).ABSTRACT: Properties of RbNO3 in (1 - x)RbNO3-xAl2O3 nanocomposites were studied by X-ray powder diffraction, electron diffraction, conductivity measurements, infrared and Raman spectroscopy, and differential scanning calorimetry. All the experimental techniques used indicate the presence of an amorphous RbNO3 layer at the RbNO3-Al2O3 interface in addition to a crystalline RbNO3 phase. Its concentration was determined from the phase transition enthalpies. The amorphous layer thickness estimated by means of a simple brick-wall model is 4 nm.4. Yuzyuk Yu.I., Farhi R., Lorman V.L., Rabkin L.M., Sapozhnikov L.A., Sviridov E.V., Zakharchenko I.N. “A comparative Raman study of ferroelectric PbTiO3 single crystals and thin film prepared on MgO substrate”. J. Applied Physics 1998, v. 84, p. 452-457.Цит. 35. (IF 1.729).ABSTRACT: A Raman study of a highly oriented PbTiO3 thin film deposited on a MgO single crystal has been performed as a function of the temperature. The results have been compared with those obtained from a single crystal prepared from the same batch and those reported in the literature for polycrystalline thin films and single crystals. A shift in the transition temperature is observed from the soft mode behavior, together with more usual lower values of its frequency, which are both related to effective hydrostatic pressure due to the clamping of grains by their neighbors in the distorted tetragonal structure. The large soft mode linewidth and its integrated intensity, which do not vanish at the ferroelectric to paraelectric transition temperature, have been interpreted in terms of the coupling of this mode (and more generally of all polar phonons) with the static strain fields originating from the clamping effect and the epitaxial conditions.5. El Marssi M., Farhi R., Yuzyuk Yu.I. “Polarized Raman and electrical study of single crystalline titanium modified lead magnesio-niobate”. J. Phys.: Condens. Matter 1998, v.10, p. 9161-9171.Цит 21. (IF 1.645).ABSTRACT: Raman scattering experiments were performed on the relaxor ferroelectric lead magnesio-niobate (PMN), the ferroelectric 0.8 PMN–0.2 PbTiO3 (PT) and the intermediate composition 0.9 PMN–0.1 PT. In order to understand in more detail the behaviour of this series, Raman scattering spectra were also collected under dc electric field. A ferroelectric phase could be induced in the latter composition for electric fields higher than a threshold value. The behaviour of this field-induced phase was compared with the (zero-field) ferroelectric phase in 0.8 PMN–0.2 PT. Barkhausen jumps were observed in the pyroelectric current measurements, and a strong dielectric anomaly was detected in zero field heating after field cooling experiments on 0.9 PMN–0.1 PT. These results are consistent with a description of the behaviour in this series based on a cancellation of 1:1 (Mg:Nb) domain random fields by titanium ions, favouring the onset of long range ferroelectric order.6. Petzelt J., Ostapchuk T., Gregora I., Rychetsky I., Hoffmann-Eifert S., Pronin A.V., Yuzyuk Y., Gorshunov B.P., Kamba S., Bovtun V., Pokorny J., Savinov M., Porokhonskyy V., Rafaja D., Vanek P., Almeida A., Chaves M.R., Volkov A.A., Dressel M., and Waser R. Dielectric, infrared, and Raman response of undoped SrTiO3 ceramics: Evidence of polar grain boundaries. Phys. Rev.B 2001, v.64, p.184111-1-10. Цит. 108. (IF 3.070).ABSTRACT: Thorough Raman and infrared (IR) reflectivity investigations of nominally pure SrTiO3 ceramics in the 10–300 K range have revealed a clear presence of the polar phase whose manifestation steeply increases on cooling. The Raman strengths of the Raman-forbidden IR modes are proportional to ω(TO1)-α (α @ 1.6) where ω(TO1) is the polar soft mode frequency. No pronounced permittivity dispersion is observed below the soft mode frequency so that, as in single crystals, the static permittivity is essentially determined by the soft mode contribution. A theory is suggested which assumes a frozen dipole moment connected with the grain boundaries which induces the polar phase in the grain bulk in correlation with the bulk soft-mode frequency. This stiffens slightly the effective soft mode response and reduces the low-temperature permittivity compared to that of single crystals. Moreover, the polar soft mode strongly couples to the Eg component of the structural soft doublet showing that the polar axis is perpendicular to the tetragonal axis below the structural transition whichis shifted to 132 K in our ceramics. Whereas the TiO6 octahedra tilt (primary order parameter) below the structural transition corresponds to that in single

crystals, much smaller A1g-Eg splitting of the structural soft doublet shows that the tetragonal deformation (secondary order parameter) is nearly 10 times smaller, apparently due to the grain volume clamping in ceramics.7. Yuzyuk Yu. I., Alyoshin V. A., Zakharchenko I. N., Sviridov E. V., Almeida A., Chaves M. R.,“Polarization-dependent Raman spectra of heteroepitaxial (Ba,Sr)TiO3/MgO thin films” Phys. Rev. B 2002, v. 65, p.134107-1-9.Цит. 35. (IF 3.272).ABSTRACT: We have studied the concentration dependence of the Raman spectra of heteroepitaxial (Ba1-

xSrx)TiO3 (BST) (x = 0.15, 0.30, and 0.45) thin films deposited by rf sputtering on (001) MgO substrates. It is found that substitution of Ba by Sr leads to the distortions of the Ti-O bonds and causes the appearance of new bands in the Raman spectra near the bands corresponding to the Ti-O vibrations. The Sr incorporation inducesrelatively large shifts of the low-frequency Raman peaks attributed to E(TO) and A1 (TO) components of the soft mode. The E (TO) soft mode in BST films becomes underdamped for x>0.3 and is very sensitive to the two-dimensional compressive stresses.8. Yuzyuk Yu. I., Simon P., Alyoshin V. A., Zakharchenko I. N., Sviridov E. V. “Stress effect on the ferroelectric-to-paraelectric phase transition in heteroepitaxial (Ba,Sr)TiO3/MgO thin film studied by Raman scattering and x-ray diffraction” Phys. Rev. B 2002, v. 66, p.052103-1-4.Цит. 35. (IF 3.272).ABSTRACT: We report experimental evidence for the stress-induced tetragonal symmetry of the paraelectric phase in heteroepitaxial (Ba0.7Sr0.3)TiO3 thin film deposited on the (001)MgO substrate. Our Raman and x-ray diffraction data evidently show that symmetry of the paraelectric phase is tetragonal well above the Curie temperature due to the two-dimensional compressive stresses imposed on the film by the substrate. On approaching the deposition temperature the thermoelastic compressive stresses vanish and Raman measurements revealed cubic symmetry of the paraelectric phase.9. Yuzyuk Yu. I., Sauvajol J.L., Simon P., Lorman V.L., Alyoshin V. A., Zakharchenko I. N., Sviridov E. V. “Phase transitions in (Ba0.7Sr0.3)TiO3/(001)MgO thin film studied by Raman scattering”. J. Appl. Phys. 2003, v. 93, p. 9930-9937.Цит. 22. (IF 3.281).ABSTRACT: Polarized Raman spectra of heteroepitaxial (Ba0.7Sr0.3)TiO3 thin film deposited on the (001)MgO substrate have been studied in the broad temperature range from 30 to 1300 K. Our results show that the ferroelectric–paraelectric phase transition is markedly shifted to higher temperatures with respect to the bulk ceramics of the same composition. Because of the two-dimensional compressive stresses imposed on the film by the substrate, the symmetry of the paraelectric phase is found to be tetragonal well above the Curie temperature. Near the deposition temperature (1173 K), the thermoelastic compressive stresses vanish and Raman response suggests nearly cubic symmetry. Raman measurements below room temperature show clearly that the phase transition to the rhombohedral phase is completely suppressed and only one phase transition from the tetragonal to the monoclinic phase is revealed at ~150 K.10. Yuzyuk Yu. I., Katiyar R. S., Alyoshin V. A., Zakharchenko I. N., Markov D. A., and Sviridov E. V. “Stress relaxation in heteroepitaxial (Ba,Sr)TiO3/(001)MgO thin film studied by micro-Raman spectroscopy”. Phys. Rev. B 2003, v. 68, p. 104104-1-4.Цит. 28. (IF 2.962).ABSTRACT: The evolution of stresses in a heteroepitaxial (Ba0.7Sr0.3)TiO3/(001)MgO thin film was studied by means of micro-Raman spectroscopy. A small part of the substrate was gradually dissolved, then partially unsupported and completely free-standing areas of the film were studied in a side-view backscattering geometry. The E(TO) soft mode was used to estimate local stresses in the thin film. Our experiments revealed stress relaxation and the gradient of the tetragonal distortion in the partially unsupported ferroelectric thin film. The length scale over which the stress relaxes in the heteroepitaxial film was estimated. The thermal strain arising mostly due to the difference between the thermal-expansion coefficients of the film and the substrate governs the domain structure and induces enhanced tetragonality in the film studied. We found that the partially unsupported thin film is polarization graded due to the stress gradient along the film-substrate interface.11. Yuzyuk Yu. I., Gagarina E., Simon P., Reznitchenko L.A., Hennet L., and Thiaudière D. “Synchrotron x-ray and Raman scattering investigations of (LixNa1-x)NbO3 solid solutions: Evidence of the rhombohedral phase”. Phys. Rev. B 2004, v. 69, p. 144105-1-7.Цит. 12. (IF 3.185).

ABSTRACT: The (LixNa1-x)NbO3 perovskite solid solutions are investigated using synchrotron x-ray diffraction and Raman spectroscopy in order to clarify the structural changes in the concentration range 0<x<0.145 at room temperature. The orthorhombic antiferroelectric P phase (space group Pbma, Z=8) exists up to x=0.02 and in the concentration interval 0.02<x<0.03 we have confirmed a previously reported transition to the orthorhombic ferroelectric Q phase (space group P21ma, Z=4). It is found that the Q phase is stable up to x=0.145 but in the narrow concentration interval at x=0.12 the dominating (86.2%) rhombohedral N phase (space group R3c, Z=2) coexists with the minor (13.8%) Q phase at room temperature. The crystal structure of this rhombohedral N phase has been refined using Rietveld method. Detailed comparison with similar low-temperature phase of pure NaNbO3 showed that the NbO6 octahedra are slightly distorted in the solid solution with x=0.12 while they are rather regular in NaNbO3. Raman spectra showed drastic changes associated with the P-Q transition and revealed coexistence of the P and Q phases in the interval 0.02<x<0.03. Abrupt transformation of the Raman response and remarkable narrowing of the Nb-O stretching vibrations related to the existence of the rhombohedral N phase at x=0.12 were observed.12. Das R.R., Yuzyuk Yu. I., Bhattacharya P., Gupta V., and Katiyar R.S. “Folded acoustic phonons and soft mode dynamics in BaTiO3/ SrTiO3 superlattices”. Phys. Rev. B 2004, v. 69, p. 132302-1-4. Цит. 12. (IF 3.185).ABSTRACT: A series of BaTiO3 /SrTiO3 superlattices with stacking periodicity of 6–10 unit cells were fabricated on (001)MgO substrates using pulsed-laser-deposition technique. Polarized Raman spectra revealed BaTiO3-like optical vibrations and confirmed tetragonal symmetry of the superlattices with the c axis being normal to the layers. Due to in-plane compressive stresses generated by the lattice mismatch of the constituting layers, the E(1TO) soft mode was underdamped and markedly shifted to higher frequencies with respect to its analogs in the bulk. The existence of perfect superlattice structure was evident from the observation of the folded acoustic phonons in Raman spectra. The frequencies of the folded phonons matched well with the calculated transverse acoustic branches of the constituent materials. No phase transitions were revealed in the superlattices below room temperature, while phase transition to the paraelectric state is shifted up to 650–700 K and it is diffused.13. Prosandeev S. A., Cockayne E., Burton B. P., Kamba S., Petzelt J., Yuzyuk Yu. I., Katiyar R.S., Vakhrushev S.B. “Lattice dynamics in PbMg1/3Nb2/3O3”. Phys. Rev. B 2004, v. 70, p. 134110-1-11.Цит. 59. (IF 3.185).ABSTRACT: Lattice dynamics for five ordered PbMg1/3Nb2/3O3 supercells were calculated from first principles by the frozen phonon method. Maximal symmetries of all supercells are reduced by structural instabilities. Lattice modes corresponding to these instabilities, equilibrium ionic positions, and infrared reflectivity spectra were computed for all supercells. Results are compared with our experimental data for a chemically disordered PMN single crystal.14. Yu I Yuzyuk, P Simon, E Gagarina, L Hennet, D Thiaudiere, V I Torgashev, S I Raevskaya, I P Raevskii, L A Reznitchenko, J L Sauvajol. Modulated phases in NaNbO3: Raman scattering, synchrotron x-ray diffraction, and dielectric investigations.// J. Phys.: Condens. Matter 2005. V.17. P.4977–4990.Цит. 21. (IF 2.145).ABSTRACT: Raman spectra of sodium niobate (NaNbO3) were obtained in all phases and revealed a significant disorder in the high-temperature U, T2 and T1 phases and a complicated folding of the Brillouin zone at the transitions into modulated S, R, P and N phases associated with the competitive zone-boundary soft modes (in-phase and out-of phase octahedral tilts) along the M–T–R line. An extensive Raman study combined with x-ray diffraction (XRD) and dielectric measurements confirmed the presence of the incommensurate (INC) phase in sodium niobate. XRD experiments revealed the invar effect in the temperature interval 410–460Kcorresponding to the INC phase associated with rotations of the NbO6 octahedra modulated along the b-direction. Our experiments suggest that the phase P consists of three phases: monoclinic (Pm)between 250 and 410 K, INC between 410 and 460 K, and orthorhombic (Po)between 460 and 633 K. At the low-temperature transition to the ferroelectric rhombohedral N phase all folded modes originating from the M- and T-points of the Brillouin zone abruptly disappear, Raman spectra in the N phase become much simpler and all peaks were assigned.

15. M. Jain, Yu. I. Yuzyuk, R. S. Katiyar, Y. Somiya, A. S. Bhalla. Local symmetry breaking in PbxSr1-

xTiO3 ceramics and composites studied by Raman spectroscopy.// Journal of Applied Physics 2005. V. 98, P.024116. Цит. 11. (IF 2.498)ABSTRACT: Local symmetry breaking in PbxSr1−xTiO3 (PST) solid solutions was revealed by Raman spectroscopy below and above the ferroelectric phase-transition temperature. In the paraelectric phase, local symmetry breaking associated with the polar clusters localized mostly at grain boundaries in ceramic samples leads to the activation of the polar modes far above the dielectric maximum. This effect was found remarkably enhanced in the PST:MgO composites due to the compositional inhomogeneity of the grain boundaries and the intergrain stresses in the composite. In the ferroelectric phase, the degeneracy of the E(TO1) soft mode was lifted due to translational symmetry breaking in the solid solutions with x=0.2 and 0.3, where the substitution of Sr by Pb replaces partially the ionic bonding between the A cations and the oxygens by a stronger covalent bonding.16. Gupta V., Bhattacharya P., Yuzyuk Yu. I., Sreenivas K., Katiyar R.S. “Optical phonon modes in ZnO nanorods on Si prepared by pulsed laser deposition” Journal of Crystal Growth 2006, v. 287, p. 39–43.Цит. 39. (IF 1.726).ABSTRACT: An array of vertically aligned c-axis-oriented zinc oxide (ZnO) nanorods were fabricated at a low substratetemperature (500 oC) without using any catalytic template on the Si substrate by pulsed laser deposition at a high pressure (1–5 Torr). The successive deposition of ZnO nanoparticles one over the other during growth led to the formation of elongated and well-isolated nanorods with a diameter in the range 70–350nm and up to 14 mm long. The influence of deposition parameters on the Raman phonon modes was investigated. The polarized Raman studies were carried out in the backward geometry with incident light (i) parallel and (ii)perpendicular to the nanorod length. The activation of lower and upper surface phonon modes were observed in the ZnO nanorods between the transverse optical (ωTO) and the longitudinal optical (ωLO) phonon frequencies. The lower surface mode observed at ~475 cm-1 is found to be predominant in the X(ZZ)X configuration. The surface phonon modes were not found in the samples prepared at >600 oC due to the coalescence process resulting in a continuous film. The agreement of polarized Raman spectra with single crystal data indicates the growth of good quality ZnO nanorods, and allows direct integration on Si without introducing contamination at the interface due to any catalytic material.17. V. B. Shirokov, Yu. I. Yuzyuk, B. Dkhil, V. V. Lemanov. Phenomenological theory of phase transitions in epitaxial BaTiO3 thin films // Physical Review B75, 224116 (2007).Цит. 21.(IF 3.17).ABSTRACT: We develop a phenomenological thermodynamic theory of ferroelectric BaTiO3 (BT) thin films epitaxially grown on cubic substrates using the Landau-Devonshire eight-order potential. The constructed “misfittemperature” phase diagram is asymmetrical. We found that the overall view of the phase diagram depends on the values of compliances used in calculations and we provide two qualitatively different diagrams. A thermodynamic path for BT film grown onto a particular substrate can be found using a plot of the room-temperature tetragonal distortion (c−a) /a as a function of misfit strain.18. Shirokov V.B., Yuzyuk Yu.I., Dkhil B., Lemanov V.V. Phenomenological theory of phase transitions in epitaxial BaxSr1-xTiO3 thin films. Physical Review B79, 144118, (2009).Цит. 15.(IF 3.322)ABSTRACT: A phenomenological thermodynamic theory of BaxSr1−xTiO3 (BST-x) thin films epitaxially grown on cubic substrates is developed using the Landau-Devonshire approach. The eighth-order thermodynamic potential for BaTiO3 (BT) single crystal and modified fourth-order potential for SrTiO3 single crystal were used as starting potentials for the end members of the solid solution with the aim to develop potential of BST-x solid solution valid at high temperatures. Several coefficients of these potentials for BT were changed to obtain reasonable agreement between theory and experimental phase diagram for BST-x (x>0.2) solid solutions. For low Ba content we constructed the specific phase diagram where five phases converge at the multiphase point (TN2=48 K, x=0.029) and all transitions are of the second order. The “concentration-misfit strain” phase diagrams for BST-x thin films at room temperature and “temperature-misfit strain” phase diagrams for particular concentrations are constructed and discussed. Near TN2 coupling between polarization and structural order parameter in the epitaxial film is modified considerably and large number of new phases not present in the bulkmaterials appear on the phase diagram.

19. Yuzyuk Yu.I., Shakhovoy R.A., Raevskaya S.I., Raevski I.P., Marssi M. El, Karkut M.G., Simon P. Ferroelectric Q-phase in NaNbO3 epitaxial thin film // Appl. Phys. Lett.- 2010. V.96. –P. 222904.Цит. 5. (IF 3.82)ABSTRACT: Epitaxial NaNbO3 thin films have been grown by pulsed laser deposition on cubic (00l) MgO substrate with epitaxial (La0.5Sr0.5)CoO3 buffer layer. Micro-Raman spectroscopy studies revealed that the ferroelectric Q phase (Pmc21, Z=4) is stable in a 250-nm-thick film in contrast to the antiferroelectric phase P (Pbma, Z=8) known to exist in the bulk single crystals and ceramics of undoped stoichiometric NaNbO3. Temperature-dependent Raman spectra indicate that the Q phase is stable over a wide temperature range (at least from 80 to 600 K), while the low-temperature ferroelectric rhombohedral phase N, typical for NaNbO3 single crystals, is not observed.20. Levshov D. I., Yuzyuk Yu. I., Michel T., Voisin C., Alvarez L., Berger S., Roussignol P., Sauvajol J.-L. Raman Probing of Uniaxial Strain in Individual Single-Wall Carbon Nanotubes in a Composite Material. // J. Phys. Chem. C -2010,V.114,P.16210–1621. (IF 4.805)ABSTRACT: The temperature dependence of the Raman spectrum of a gelatin-based composite material doped with singlewalled carbon nanotubes (SWNT@gelatin) is reported. A significant upshift of the G-mode frequency is observed when the temperature is decreased from room temperature to 20 K. This frequency shift is significantly stronger than the one found for pure thermal effects. In contrast, the features of the radial breathing modes (frequencies and width) display no significant change in the same temperature range. These results are well understood by considering a uniaxial strain on the nanotube induced by the thermal expansitivity mismatch between the nanotube and the surrounding matrix.21. A.S. Anokhin, Yu.I. Yuzyuk, Yu.I. Golovko, V.M. Mukhortov, and M. El Marssi, Electric-field-induced monoclinic phase in (Ba,Sr)TiO3 thin film // J. Appl. Phys. 109, 074111 (2011). (IF 2.168)ABSTRACT: We have studied electric-field-induced symmetry lowering in the tetragonal (001)-oriented heteroepitaxial (Ba0,8Sr0,2)TiO3 thin film deposited on (001)MgO substrate. Polarized micro-Raman spectra were recorded from the film area in between two planar electrodes deposited on the film surface. Presence of c domains with polarization normal to the substrate was confirmed from polarized Raman study under zero field, while splitting and hardening of the E(TO) soft mode and polarization changes in the Raman spectra suggest monoclinic symmetry under external electric field.22. N. Ortega, A. Kumar, O.A. Maslova, Yu.I. Yuzyuk, J.F. Scott, R.S. Katiyar. Effect of periodicity and composition in artificial BaTiO3/(Ba,Sr)TiO3 superlattices //Phys. Rev. B83, 144108 (2011).Цит. 7. (IF 3.691)ABSTRACT: We have prepared two series of BaTiO3/SrTiO3 (BT/ST) superlattices (SLs). In the first set, the modulation period (Λ) was varied from 136 to 16 A°, whereas in the second set ST was replaced with Ba(1−x)SrxTiO3 (BST) (0 < x <1) with constant periodicity of ∼ 136 A° . A total stack height of 10 000 A° (1 μm) was maintained for both systems. The compositional changes give large spectral changes at x = 40% where the lowest E mode in BT/BST SL becomes underdamped. X-ray-diffraction patterns and surface topography of the modulated period revealed a Stranski-Krastanov growth mechanism. The upward frequency shift of the E(1TO) in SLs with decrease in Λor Ba concentration in the BST layer was attributed to the in-plane compressive stress induced by the lattice mismatch of the constituent layers. [N.B., here the notation E(1TO) or A1(2TO) simply designates the vibrational mode of E or A1 symmetry, with 1TO or 2TO designating the transverse optical branch that is lowest, 1, or second lowest, 2, in energy.] In the low-frequency region, the folded acoustic phonon doublets were observed. Since the low-frequency out-of-plane dielectric constant is directly related to the E(1TO) soft mode frequency, strain engineering in artificial SLs allowed us to modify their dielectric properties by varying either the Ba/Sr in BST sublayer concentration or the modulation periodicity in the superlattices.23. D. Levshov, T. Than, R. Arenal, V. N. Popov, R. Parret, M. Paillet, V. Jourdain, A. A. Zahab, T. Michel, Yu. I. Yuzyuk, J.-L. Sauvajol. Experimental evidence of a mechanical couplingbetween layers in an individual double-walled carbon nanotube // NanoLetters, 2011, -V.11, -P.4800-4804 (IF 13.198)ABSTRACT: We perform transmission electron microscopy, electron diffraction, and Raman scattering experiments on an individual suspended double-walled carbon nanotube (DWCNT). The first two techniques allow the unambiguous determination of the DWCNT structure: (12,8)@(16,14). However, the low-frequency features in the Raman spectra cannot be connected to the derived layer diameters d by

means of the 1/d power law, widely used for the diameter dependence of the radial-breathing mode of single-walled nanotubes. We discuss this disagreement in terms of mechanical coupling between the layers of the DWCNT, which results in collective vibrational modes. Theoretical predictions for the breathing-like modes of the DWCNT, originating from the radial-breathing modes of the layers, are in a very good agreement with the observed Raman spectra. Moreover, the mechanical coupling qualitatively explains the observation of Raman lines of breathing-like modes, whenever only one of the layers is in resonance with the laser energy.

Evgeniy KAIDASHEV (h=15)1. Bundesmann C., Schubert M., Spemann D., Butz T., Lorenz M., Kaidashev E. M., Grundmann M., Ashkenov N., Neumann H., Wagner G. Infrared dielectric functions and phonon modes of wurtzite MgxZn1-xO (x<=0.2) // Appl. Phys. Lett.- 81.-2002.-p. 2376-2378 (IF=3.844)ABSTRACT: Infrared dielectric function spectra and phonon modes with polarization parallel and perpendicular to the c axis of high quality, highly relaxed, and single crystalline wurtzite MgxZn1-xO films with 0<x<0.2 prepared by pulsed-laser deposition on c-plane sapphire substrates were obtained from infrared spectroscopic ellipsometry (380–1200 cm-1) and Raman scattering studies. A two-mode behavior is found for the modes with E1 symmetry, a lattice mode and an impurity-type mode are obtained for the A1 symmetry phonons. Model dielectric function spectra will become useful for future infrared ellipsometry analysis of complex Mgx Zn1-xO-based heterostructures.2. Ashkenov N., Wagner G., Neumann H., Mbenkum B. N, Bundesmann C., Riede V., Lorenz M., Kaidashev E. M., Kasic A., Schubert M., Grundmann M. Infrared dielectric functions and phonon modes of high-quality ZnO films // J. Appl. Phys.- 93.-2003.-p. 126-133(IF=2.168)ABSTRACT: Infrared dielectric function spectra and phonon modes of high-quality, single crystalline, and highly resistive wurtzite ZnO films were obtained from infrared (300–1200 cm-1) spectroscopic ellipsometry and Raman scattering studies. The ZnO films were deposited by pulsed-laser deposition on c-plane sapphire substrates and investigated by high-resolution x-ray diffraction, high-resolution transmission electron microscopy, and Rutherford backscattering experiments. The crystal structure, phonon modes, and dielectric functions are compared to those obtained from a single-crystal ZnO bulk sample. The film ZnO phonon mode frequencies are highly consistent with those of the bulk material. A small redshift of the longitudinal optical phonon mode frequencies of the ZnO films with respect to the bulk material is observed. This is tentatively assigned to the existence of vacancy point defects within the films. Accurate long-wavelength dielectric constant limits of ZnO are obtained from the infrared ellipsometry analysis and compared with previously measured near-band-gap index-of-refraction data using the Lyddane–Sachs–Teller relation. The ZnO model dielectric function spectra will become useful for future infrared ellipsometry analysis of free-carrier parameters in complex ZnO-based heterostructures.3.Schmidt R., Rheinländer B., Schubert M., Spemann D., Butz T., J. Lenzner, E. M. Kaidashev, M. Lorenz, A. Rahm, H. C. Semmelhack, and M. GrundmannDielectric functions „(1 to 5 eV)… of wurtzite MgxZn1-x O (x≤0.29) thin films// Appl. Phys. Lett. –82.- No. 14.-2003.- 2260-2262(IF=3.844) ABSTRACT: The optical dielectric functions for polarization perpendicular and parallel to the c-axis ~optical axis of pulsed-laser-deposition grown wurtzite MgxZn1-xO (0<x<0.29) thin films have been determined at room temperature using ellipsometry for photon energies from 1 to 5 eV. The dielectric functions reveal strong excitonic contributions for all Mg concentrations x. The band gap energies (E0

A =3.369 eV for ZnO to 4.101 eV for x=0.29) show a remarkable blueshift. The exciton binding energy (61 meV for ZnO) decreases to approximately 50 meV for x=0.17 and increases to approximately 58 meV for x=0.29. In contrast to ZnO, the MgxZn1-xO alloys are found uniaxial negative below the band gap energy, opposite to previously reported results.4. Kaidashev E. M., Lorenz M., Wenckstern H., Benndorf G., Rahm A., Semmelhack H.-C., Han K.-H., Hochmuth H., Bundesmann C., Riede V., Grundmann M., High electron mobility of epitaxial ZnO thin films on c-plane sapphire grown by multi-step pulsed laser deposition, Appl. Phys. Lett. 82 No. 22 (2003) 3901-3. (IF=3.844)

ABSTRACT: A multistep pulsed-laser deposition PLD process is presented for epitaxial, nominally undoped ZnO thin films of total thickness of 1 to 2 mm on c-plane sapphire substrates. We obtain reproducibly high electron mobilities from 115 up to 155 cm2 /Vs at 300 K in a narrow carrier concentration range from 2 to 5x1016 cm-3. The key issue of the multistep PLD process is the insertion of 30-nm-thin ZnO relaxation layers deposited at reduced substrate temperature. The high-mobility samples show atomically flat surface structure with grain size of about 0.5–1 mm, whereas the surfaces of low-mobility films consist of clearly resolved hexagonally faceted columnar grains of only 200-nm size, as shown by atomic force microscopy. Structurally optimized PLD ZnO thin films show narrow high-resolution x-ray diffraction peak widths of the ZnO(0002) w- and 2q-scans as low as 151 and 43 arcsec, respectively, and narrow photoluminescence linewidths of donor-bound excitons of 1.7 meV at 2 K.5. Bundesmann C., Ashkenov N. , Schubert M., Spemann D., Butz T. , Lorenz M., Kaidashev E. M., Grundmann M. Raman scattering in ZnO thin films doped with Fe, Sb, Al, Ga and Li //Appl. Phys. Lett.- 83.- No.10.-2003.- 1974-1976(IF=3.844)ABSTRACT: Polarized micro-Raman measurements were performed to study the phonon modes of Fe, Sb, Al, Ga, and Li doped ZnO thin films, grown by pulsed-laser deposition on c-plane sapphire substrates. Additional modes at about 277, 511, 583, and 644 cm21, recently assigned to N incorporation [A.Kaschner et al., Appl. Phys. Lett. 80, 1909 (2002)], were observed for Fe, Sb, and Al doped films, intentionally grown without N. The mode at 277 cm-1 occurs also for Ga doped films. These modes thus cannot be related directly to N incorporation. Instead, we suggest host lattice defects as their origin. Further additional modes at 531, 631, and 720-1 seem specific for the Sb, Ga, and Fe dopants, respectively. Li doped ZnO did not reveal additional modes.6. Lorenz M., Kaidashev E. M., Wenckstern H., Riede V., Bundesmann C., Spemann D., Benndorf G., Hochmuth H., Rahm A., Semmelhack H.-C., Grundmann M.Optical and electrical properties of epitaxial (Mg, Cd)xZn1-xO, ZnO, and ZnO:(Ga, Al) thin films on c-plane sapphire grown by pulsed laser deposition // Solid State Electronics.- 2003.-47.-p. 2205-2208(IF=1.397)ABSTRACT: A consistent set of epitaxial, n-type conducting ZnO thin films, nominally undoped, doped with Ga or Al, or alloyed with Mg or Cd, was grown by pulsed laser deposition (PLD) on single-crystalline c-plane sapphire (0 0 0 1) substrates, and characterized by Hall measurement, and UV/VIS optical transmission spectroscopy. The optical band gap of undoped ZnO films at nearly 3.28 eV was shifted by alloying with Mg up to 4.5 eV and by alloying with Cd down to 3.18 eV, dependent on the alloy composition. In addition, highly doped ZnO:Al films show a blue-shifted optical absorption edge due to filling of electronic states in the conduction band. The Hall transport data of the PLD (Mg,Zn,Cd)O:(Ga,Al) thin films span a carrier concentration range of six orders of magnitude from 3x1014 to 3x1020 cm-3 , which corresponds to a resistivity from 5x10-4 to 3x10-3 Wcm. Structurally optimized, nominally undoped ZnO films grown with ZnO nucleation and top layer reached an electron mobility of 155 cm2 /V s (300 K), which is among the largest values reported for heteroepitaxial ZnO thin films so far.Finally, we succeeded in combining the low resistivity of ZnO:Ga and the band gap shift of MgZnO in MgZnO:Ga thin films. This results demonstrate the unique tunability of the optical and electrical properties of the ZnO-based wideband gap material for future electronic devices.7. Schmidt-Grund R., Schubert M., Rheinländer B., Fritsch D., Schmidt H., Kaidashev E.M., Lorenz M., Hochmuth H., Grundmann M.UV-VUV Spectroscopic ellipsometry of ternary M MgxZn1-xO (0≤x≤0.53) thin films // Thin Solid Films.-2004.-v. 455-456, p.500-504(IF=1.89)ABSTRACT: The ordinary optical dielectric functions of pulsed-laser-deposition grown wurtzite c-plane MgxZn1-xO (0≤x ≤0.53) thin films have been determined by using spectroscopic ellipsometry in the photon energy range from 4.5 to 9.5 eV. The dielectric functions reveal features which resemble those previously detected in uniaxial AlGaN and identified as E1- and E2-type band-to-band transitions with no remarkable dependence of the transition energy on Mg content x. The E1- and E2-type transitions for ZnO are compared with pseudopotential band-structure calculations.8. Wenckstern H., Kaidashev E.M., Lorenz M., Hochmuth H., Biehne G., Lenzner J., Gottschalch V., Pickenhain R., Grundmann M. Lateral homogeneity of Schottky contacts on n-type ZnO // Applied Physics Letters.-2004.- 84.-p.79-81(IF=3.844)

ABSTRACT:The electrical properties of Schottky contacts (SCs) produced ex situ on n-type ZnO single crystals and epitaxial thin films were investigated. Electron beam induced current imaging was used to study lateral variations of the current induced in the space charge region of the SC. Further, the effective barrier height was determined by current–voltage and capacitance–voltage measurements. Pd contacts prepared on ZnO thin films that had undergone treatment in a plasma-enhanced chemical vapor deposition with nitrous oxide (N2O) as ambient gas are laterally homogeneous with an effective barrier height of (600± 30) meV9.Bundesmann C., Ashkenov N., Schubert M., Rahm A., Wenckstern H., Kaidashev E. M., Lorenz M., Grundmann M. Infrared dielectric functions and crystal orientation of a-plane ZnO thin films on r-plane sapphire determined by generalized ellipsometry // Thin Solid Films.- 2004.- 455-456.- p. 161-166. (IF=1.89)ABSTRACT: Generalized infrared spectroscopic ellipsometry for wave numbers from 370 to 1200 cm-1 was applied to study the anisotropic dielectric response of wurtzite-type ZnO thin films grown on r-plane sapphire.Combined wavelength-by-wavelength analysis of data measured at multiple sample in-plane orientations allows for simultaneous extraction of the dielectric function (DF) tensor, the film thickness and the respective ZnO c-axis orientation, specifically in relation to the sapphire substrate.For anisotropic materials and use of generalized ellipsometry, the correlation problem between thickness and DF does not exist.Subsequent lineshape analysis of ordinary and extraordinary DFs provides complete A1- and E1-symmetry longitudinal and transverse optical phonon-mode and broadening parameters, together with the static dielectric constants.The epitaxial relations from the ellipsometry data analysis are (1 1 -2 0) ZnO ½½(0 1 -1 2)sapphire and [0 0 0 1]ZnO ½½[0-1 1 1]sapphire, which was confirmed by XRD measurements.10.NobisT., Kaidashev E.M., Rahm A., Lorenz M., Lenzner J., Grundmann M.Spatially Inhomogeneous Impurity Distribution in ZnO Micropillars // NanoLetters.- 2004.-N. 4.- p. 797 – 800 (IF=13.198)ABSTRACT: Using ZnO a variety of micro- and nanostructures can be fabricated. We investigate hexagonal micropillars grown by high pressure pulsed laser deposition on sapphire with spatially and spectrally resolved cathodoluminescence. We demonstrate that the impurity and defect incorporation is strongly inhomogeneous, at least under the present growth conditions, dramatically influencing the optical properties.11. NobisT, Kaidashev E.M., Rahm A., Lorenz M, Grundmann M.Whispering gallery modes in nano-sized dielectric resonators with hexagonal cross section, Phys. Rev. Lett.-2004.-v.93.-N.10.-p.1039031-1039034.(IF=7.37)ABSTRACT: The size dependence of whispering gallery modes in dielectric resonators with hexagonal cross section has been observed within the visible spectral range for cavity diameters comparable to the light wavelength. As a model system single, tapered, high aspect ratio zinc oxide nanoneedles were analyzed. They enable systematic investigations as a function of the resonator diameter down to the nanometer regime. A simple plane wave interference model without free parameter describes the spectral positions and the linewidths of the modes in good agreement with the experiment.12. Speman D.,Kaidashev E.M.,Lorenz M.,Vogt J.,Butz T.Ion beam analysis of epitaxial (Mg,Cd)xZn1-xO and ZnO:(Li,Al,Ga,Sb) thin films growth on c-plane sapphire //Nuclear Instruments and Methods in Physics Research.-B.-2004.-v.219-220.-p.891-896. (IF=1.211)ABSTRACT: In this study ZnO thin films, nominally undoped, doped with Li, Al, Ga and Sb and alloyed with Mg and Cd grown epitaxially on c-plane sapphire by pulsed laser deposition (PLD) were investigated. In order to correlate the optical and electrical properties, e.g. the band gap energy and carrier concentration, to the elemental composition, the films were analyzed by RBS, PIXE and PIGE using He+ and H+ ion beams. It was found that the element transfer from the PLD target to the film differs significantly for the individual doping and alloying elements, with concentration ratios between film and target ranging from 4% for Li and Cd to 400% for Ga. In general, the films exhibited a metal to oxygen ratio of 1:1, only the ZnO:Li films were slightly oxygen deficient. Furthermore, the crystalline quality of the films was investigated using ion channeling. The nominally undoped ZnO films which were deposited with low-temperature interlayers for lower lateral stress showed a normalized minimum RBS yield of cmin= 3.3% under channeling conditions. Whereas the incorporation of isovalent alloying atoms into the ZnO films

leads to a slight degradation of the crystalline quality only, doping degrades the crystalline quality remarkably, even at low dopant concentrations.13.M. Lorenz, J. Lenzner, E.M. Kaidashev,H. Hochmuth, M.Grundmann, Cathodoluminescence of selected single ZnO nanowires on sapphire//Annalen der Physik.-2004.-V.13.-N.1-2.p. 39–42 (IF=0.841) ABSTRACT: Cathodoluminescence (CL) investigations of selected single ZnO nanowires grown by a thermal vapor-liquid-solid process demonstrate their very good structural quality. The low temperature CL of the ZnO nanowires of about 100 nm diameter shows in the spectral range of the donor bound exciton three main peaks at 3.366, 3.362, and 3.358 eV. The full width at half maximum of the bound exciton peak is 1.1 meV for ZnO nanowires at 9 K. In comparison, the peak widths of epitaxial ZnO PLD thin films and a ZnO bulk single crystal (Eagle Picher) are 1.2 meV and 0.7 meV, respectively. In contradiction to ZnO nanowires grown by MOCVD at 750°C, the CL spectra of the thermally (915°C) grown ZnO nanowires show no additional peaks from donor or acceptor transitions or phonon replica.14.M. Lorenz, H. Hochmuth, R. Schmidt-Grund, E.M. Kaidashev, M.Grundmann, Advances of pulsed laser deposition of ZnO thin films//Annalen der Physik.-2004.-V.13. - N.1-2 .- p. 59–60 (IF=0.841)ABSTRACT: Advances in Pulsed Laser Deposition (PLD) equipment and process design for the epitaxy of ZnO thin films on a-, and c-oriented sapphire substrates are reported. The achieved improvement of device relevant ZnO layer properties is directly related to our equipment design and novel process schemes. First results on growth and reflectivity of ZnO-MgO based dielectric Bragg resonators for future ZnO-based light emitter devices are shown.15.E. Guzmán, H. Hochmuth, M. Lorenz, H. von Wenckstern, A. Rahm, E.M. Kaidashev, M. Ziese, A. Setzer, P. Esquinazi, A. Pöppl, D. Spemann, R. Pickenhain, H. Schmidt, M. Grundmann, Pulsed laser deposition of Fe- and Fe, Cu-doped ZnO thin films//Annalen der Physik.-2004-V.13.N. 1-2,pages 57–58 (IF=0.841)ABSTRACT: Fe- and Fe, Cu-doped ZnO films have been grown on 10 × 10 mm2 c-plane sapphire by pulsed laser deposition (PLD). The targets were prepared from ZnO, Fe2O3, and/or CuO powder. The structural, electrical and magnetical properties of thin films grown under different conditions have been investigated. As expected, the doped ZnO thin film properties depend sensitively on the dopant material.16. M. Lorenz, E. M. Kaidashev, A. Rahm, Th. Nobis, J. Lenzner, G. Wagner,D. Spemann, H. Hochmuth, and M. Grundmann MgxZn1-xO (x<0.2)nanowire arrays on sapphire grown by high-pressure pulsed-laser deposition//Appl.Phys.Lett.2005.v. 86.p 143113-143115(IF=3.844)ABSTRACT: MgxZn1-xO nanowires with Mg-content x from 0 to 0.2 have been grown by high-pressure pulsed-laser deposition (PLD) on gold-covered sapphire single crystals. The PLD process allows for a unique wide-range control of morphology, diameter, and composition of the MgxZn1-xO nanowires. The diameter of single ZnO wires could be varied between about 50 and 3000 nm, and the Mg content x of MgxZn1-xO wire arrays was controlled via the PLD gas pressure. The microscopic homogeneity of Mg content is displayed by cathodoluminescences imaging of the excitonic peak energy. The fluctuation of CL peak energy between individual wires is about an order of magnitude smaller than the alloy broadening.17. Th. Nobis, E.M. Kaidashev, A. Rahm, M. Lorenz, M. Grundmann Whispering gallery modes in hexagonal zinc oxide micro-and nanocrystals//Zinc Oxide-A Material for Micro-and Optoelectronic Applications.2005.Springer.p.83-9818.A.Rahm, E.M. Kaidashev, H.Schmidt, M.Diaconu, A.Pöppl, R.Böttcher, Ch.Meinecke, T.Butz, M.Lorenz and M.Grundmann, Growth and Characterization of Mn- and Co-Doped ZnO Nanowires, Microchimica Acta, 2006,p.1436-5073(IF=3.033)ABSTRACT: We report on the high-pressure pulsed laser deposition growth of zinc oxide nanowires containing about 0.2 at.% Co and 0.5 at.% Mn by NiO and Au catalyst. Scanning electron microscopy and X-ray diffraction measurements revealed arrays of parallel-standingnanowires with hexagonal cross section and uniform in-plane epitaxial relations without rotational domains. Elemental analysis was carried out using particle induced X-ray emission and Q-band electron spin resonance. The valence of the incorporated Mn was determined to be 2+. Atomic and magnetic force microscopy measurements indicate that Mn is incorporatedpreferentially at the nanowire boundaries.

19.A.O.Ankiewicz,M.C.Karmo,N.A.Sobolev,W.Gehlhoff,E.M.Kaidashev,A.Rahm,M.Lorenz,M.Grundmann,Electron paramagnetic resonance in transition metal-doped ZnO nanowires//Journal Applied Physics,2007,v.101,p.0243241-0243246(IF=2.168)ABSTRACT: The wide-band-gap zinc oxide-based diluted magnetic semiconductors currently attract considerable attention due to their possible use in spintronic devices. In this work, we studied ZnO nanowire samples synthesized on 10x10 mm2a-plane sapphire substrates by high-pressure pulsed laser deposition. The samples were characterized by scanning electron microscopy (SEM) and electron paramagnetic resonance (EPR) in the X-band(~9.3 GHz) from T=4 to 300 K. According to the SEM pictures, the nanowires exhibit a length of about 1μm and are aligned perpendicular to the substrate surface. The structures have a hexagonal cross section and their diameter ranges from 60 nm up to 150 nm. For the lowest nominal concentrations of cMn =3 at. % and cCo=5 at. %, we detect the anisotropic EPR spectra of isolated Mn2+ (3d5,6S) and Co2+ (3d7,4F), respectively, on Zn sites. The detection of the well-resolved anisotropic spectra proves a coherent crystallographic orientation of the nanowires. The linewidth was larger than the best values reported in the literature.Nevertheless, it was possible to identify two different components, A and B, of the reported spectra. From the temperature dependence of the EPR intensity, we found that both components exhibit paramagnetic behavior and are present in a concentration ratio of NB/NA=1.4. In the case of the Mn-doped ZnO wires, the linewidth increases with increasing Mn concentration due to the dipole-dipole interaction of the paramagnetic ions. At the highest used nominal concentration, cMn=10 at. %, an additional broad single line is observed.20. M. Grundmann, A. Rahm, Th. Nobis, M. Lorenz, Ch.Czekalla, E. M. Kaidashev, J. Lenzner, N. Boukos, A. Travlos Growth and characterization of ZnO nano- and microstuctures in: Handbook of Self-Assembled Semiconductor Nanostructures for Novel Devices in Photonics and Electronics, M. Henini, ed. (Elsevier, Amsterdam, 2008), pp. 293-32321.Czekalla, J. Guinard, C.Hanisch, B.Q.Cao, E.M.Kaidashev,N. Boukos, A. Travlos, J. Renard, B. Gayral, D. Le. Si. Dang,M.Lorenz and M Grundmann Spatial fluctuations of optical emission from single ZnO/MgZnO nanowire quantum wells // Nanotechnology 19 (2008) 115202 (IF=3.979)ABSTRACT: MgZnO/ZnO quantum wells on top of ZnO nanowires were grown by pulsed laser deposition.Ensembles of spatially fluctuating and narrow cathodoluminescence peaks with single widths down to 1 meV were found at the spectral position of the quantum well emission at 4 K. In addition, the number of these narrow QW peaks increases with increasing excitation power in micro-photoluminescence, thus pointing to quantum-dot-like emission centers. Indeed, laterally strained areas of about 5 nm diameter were identified at the quantum well positions on top of the nanowires by high-resolution transmission electron microscopy.22.V.E. Kaydashev, E.M. Kaidashev, M. Peres, T. Monteiro, M.R. Correia, N.A. Sobolev, L.C. Alves, N. Franco, andE. Alves, Structural and optical properties of Zn0,9Mn0,1O/ZnO core-shell nanowires and Zn0,9Mn0,1O nanorods designed by pulsed laser deposition// J.Appl. Phys. 106, 093501 (2009) (IF=2.168)ABSTRACT: Core-shell ZnO/ZnMnO nanowires on a-Al2O3 and GaN (buffer layer)/Si (111) substrates were fabricated by pulsed laser deposition using a Au catalyst. Two ZnO targets with a Mn content of 10% were sintered at 1150 and 550 °C in order to achieve the domination in them of paramagnetic MnO2 and ferromagnetic Mn2O3 phases, respectively. Cluster mechanism of laser ablation as a source of possible incorporation of secondary phases to the wire shell is discussed. Raman spectroscopy under excitation by an Ar+ laser revealed a broad peak related to the Mn-induced disorder and a redshift in the A1-LO phonon. Resonant Raman measurements revealed an increase in the multiphonon scattering caused by disorder in ZnO upon doping by Mn. Besides the UV emission, a vibronic green emission band assisted by a ~71 meV LO phonon is also observed in the photoluminescence spectra. Core-shell structures with smooth shells show a high exciton to green band intensity ratio (~10) even at room temperature.23. Amélia O. Ankiewicz, Wolfgang Gehlhoff, Joana S. Martins, Ângela S. Pereira, Sérgio Pereira,Axel Hoffmann, Evgeni M. Kaidashev, Andreas Rahm, Michael Lorenz, Marius Grundmann,Maria C. Carmo, Tito Trindade, and Nikolai A. Sobolev, Magnetic and structural propertiesof transition metal doped zinc-oxide nanostructures //Phys. Status Solidi .2009.B 246, No. 4, p.766–770 (IF=1.316)ABSTRACT: We report on the magnetic and structural properties of two types of nanostructures doped with Co or Mn, namely, ZnO nanowires and colloidal ZnO nanocrystals. Electron paramagnetic resonance

(EPR) spectra have been measured and analysed to extract information on the incorporation of the ions in the lattice. A detailed analysis by means of simulations of the experimental EPR spectra confirms that the transition metal (TM) ions were mainly incorporated as TM2+, occupying the Zn2+ sites in the wurtzite structure of ZnO. Furthermore, for both types of nanostructures, the EPR spectra are composed of more than one signal, revealing locally distorted environments or core-shell structures, proved by surface modifications via inorganic coatings.24..M. Lorenz, A. Rahm, B. Cao, J. Zuniga-Perez, E. M. Kaidashev,N. Zhakarov, G. Wagner, Th. Nobis, C. Czekalla1, G. Zimmermann,M. Grundmann Self-organized growth of ZnO-based nano- and microstructures// Phys. Status Solidi B.2010.p.1–17 (IF=1.316)ABSTRACT: ZnO-based nano- and micro-structures with controlled orientation,size, and lateral density were grown by specially designed two-step pulsed laser deposition and direct carbothermal growth, respectively. Different substrate orientations and nucleation layers allow well-defined tuning of growth direction and lateral arrangement of the wires. As a result, axial MgZnO–ZnO nano quantum dots and homogeneous radial nano coreshell quantum well structures are demonstrated. Donor and acceptor doping of nano- and microwires influence considerably both electrical characteristics as well as morphology including branching. Field effect transistors with n- and p-type wire channel and nanowire p–n junctions seem to prove areproducible p-type conductivity of phosphorous-doped ZnO wires. Single ZnO wire (309 nm thick, 3.99 mm high) grown on pyramidal base with controlled lateral density by tuning theZnO template layer in a two-step PLD process.25. Ishioka K. ,Petek H. , Kaydashev V.E., Kaidashev E Mand Misochko O. V. Coherent optical phonons of ZnO under near resonant photoexcitation //J. Phys.: Condens. Matter.2010.v. 22.p. 465803(IF=2.546)ABSTRACT: Ultrafast electron–phonon coupling dynamics in ZnO are investigated by degenerate pump–probe reflectivity measurements using near resonant 400 nm light. Because of the below-gap excitation, photocarriers are excited primarily from deep levels of intrinsic point defects. At least six coherent phonon modes, including two E2 modes and their combination, longitudinal optical (LO) mode and its overtone (2LO), are observed. Unlike the previous resonant Raman studies using 325nm light, the intensity of the polar LO phonons is only moderately enhanced by the Fröhlich interaction. The non-polar E2 phonons decay considerably faster than under visible excitation, indicative of strong deformation potential interaction with photocarriers. The overdamped oscillation centered at around 20 THz is tentatively attributed to the upper branch of the plasmon–phonon coupled mode. The pump-polarization dependence of the phonon amplitudes is consistent with the impulsive Raman generation.26. Guda. A.A., Smolentsev N. , Verbeeck J. , Kaidashev E.M. , Zubavichus Y. , Kravtsova A.N. , Polozhentsev O.E., Soldatov A.V.X-ray and electron spectroscopy investigation of the core–shell nanowires of ZnO:Mn//Solid State Communications. 2011.v. 151.p. 1314–1317(IF=1.649)ABSTRACT: ZnO/ZnO:Mn core–shell nanowires were studied by means of X-ray absorption spectroscopy of the Mn K- and L2,3-edges and electron energy loss spectroscopy of the O K-edge. The combination of conventional X-ray and nanofocused electron spectroscopies together with advanced theoretical analysis turned out to be fruitful for the clear identification of the Mn phase in the volume of the core–shell structures. Theoretical simulations of spectra, performed using the full-potential linear augmented plane wave approach, confirm that the shell of the nanowires, grown by the pulsed laser deposition method, is a real dilute magnetic semiconductor with Mn2+atoms at the Zn sites, while the core is pure ZnO.