Complex Fluids Group University of São Paulo, Brazil LYO-BANANA MESOPHASES COMPOSED BY A MIXTURE OF APOLAR SOLVENTS AND BENT- SHAPED MOLECULES O. G. Martins 1 , Y. Huang 2 , A. Jákli 2 , H. Sawade 2 e A. M. Figueiredo Neto 1 1 Instituto de Física, Universidade de São Paulo, Brazil 2 Liquid Crystal Institute, Kent State University, USA
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Complex Fluids Group University of São Paulo, Brazil
LYO-BANANA MESOPHASES COMPOSED BY A MIXTURE OF APOLAR SOLVENTS AND BENT-SHAPED MOLECULES. Complex Fluids Group University of São Paulo, Brazil. O. G. Martins 1 , Y. Huang 2 , A. Jákli 2 , H. Sawade 2 e A. M. Figueiredo Neto 1 1 Instituto de Física, Universidade de São Paulo, Brazil - PowerPoint PPT Presentation
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Complex Fluids GroupUniversity of São Paulo,
Brazil
LYO-BANANA MESOPHASES COMPOSED BY A MIXTURE OF APOLAR SOLVENTS AND BENT-
SHAPED MOLECULES
O. G. Martins1, Y. Huang2, A. Jákli2, H. Sawade2 e A. M. Figueiredo Neto1
1Instituto de Física, Universidade de São Paulo, Brazil2Liquid Crystal Institute, Kent State University, USA
Complex Fluids GroupUniversity of São Paulo,
Brazil
Molecules with the “form” of
H
N
O
O
RR
N
O
O
H
R R
O
O
H H
N N
O
O
H
N
O
O
O O
N
O
O
H
9’
10’
128
5
1
23
4
67
9
1011
B
AA’
B ’
long axis C
1996
1925
Complex Fluids GroupUniversity of São Paulo,
Brazil
(+) Chirality
Synclin icAntiferro
Anticlin icFerro
Anticlin icAntiferro
Synclin icFerro
Racemic
E = 0 E = 0E < -E t h E < -E thE > E th E > E th
C
z
z
bn
c
b
BA Homogeneouslychiral
(- ) Chirality
Complex Fluids GroupUniversity of São Paulo,
Brazil
a
c B1 phase of the “smectic type”
k
m
n n
n
n
n
n
n
n
m
m
m
m
m
m
m
C P
C B2
C B1
C G
z
y x
z
Complex Fluids GroupUniversity of São Paulo,
Brazil
Bi ,with i from 1 to 7
B2 B5 smectic, with 2D rectangular ordering in the layers
1) With ferroelectric switching
(symmetry C2v), smectic
2) 2D ordering
B1 smectic, with 2D rectangular ordering in the layers
B7 structure not well determined [probably of the type
1) above]
Complex Fluids GroupUniversity of São Paulo,
Brazil
3) phases with intercalated molecules
B6 smectic , with tilted molecules
4) Crystalline phases
B3 and B4
Complex Fluids GroupUniversity of São Paulo,
Brazil
xilene molecular mass: 108
Complex Fluids GroupUniversity of São Paulo,
Brazil
B7 phase in the temperaturerange from 90 to 133oC
Smectic with spacing layer of38.5Å, and a complex in-layerstructure. Helical filaments atthe transition from the ISO phase.-“telephone-wire-like” texture