Microwave spectroscopy of the heavy-atom carbene analog HSiI and DSiI Lu Kang Southern Polytechnic State University Marietta, GA Mohammed A. Gharaibeh.

Microwave spectroscopy of the heavy-atom carbene analog

HSiI and DSiI

Lu KangSouthern Polytechnic State University

Marietta, GA

Mohammed A. Gharaibeh and Dennis J. ClouthierUniversity of Kentucky, Lexington, KY

Stewart E. NovickWesleyan University, Middletown, CT

Dennis Clouthier (pronounced Clue-chay)

Pete Pringle (pronounced Pringle) & Lu Kang

Jim Cederberg, St. Olaf College

Lu is at St. Olaf learning to use Jim’sMBER (originally Norman Ramsey’s)

H3SiI in a methanol/dry ice bath held between -40 and -50 C, P ~ 5 torr

5 torr H3SiI in 2 atm of Ne, discharge of -1000 V immediately followingsupersonic expansion to produce HSiI (or DSiI if we start with D3SiI)

2/3

Spectroscopic constants of HSiI as measured by FTMW spectroscopy

The r0 structure of HSiI

1.5405 A

92.68 o

2.4614 A

This work Clouthier et al a

r0(H – Si) 1.5405(16) Å 1.534(1) Å

r0(Si – I) 2.46143(9) Å 2.463(1) Å

θ0(HSiI) 92.68(6)° 92.4(1)°

a. D.J. Clouthier, W.W. Harper, C.M. Klusek, T.C. Smith, J. Chem. Phys. 109, 7827 (1998), jet-cooled pulsed-discharge

HSiCl a HGeCl b HGeBr c HSiI d

Bond angle

95o 95.3o 94.1o 92.7 o

(Xbb-Xcc) Xaa

-1.185e -1.025e -0.965 -0.914

a. W. Lin, S. E. Novick, M. Fukushima, W. Jäger, J. Phys. Chem. A 106, 7703 (2002), D.A. Hostutler, N. Ndiege, D.J. Clouthier, S.W. Pauls, J. Chem. Phys. 115, 5485 (2001)b. W. Lin, L. Kang, S.E. Novick, J. Mol. Spectrosc. 230, 93 (2005)c. L. Kang, F. Sunahori, A.J. Minei, D.J. Clouthier, S.E. Novick, J. Chem. Phys. 130, 24317 (2009)d. This worke. B3LYP/aug-cc-pvqz

b

a

c

χaa=-795.744 MHz

χbb=+833.330 MHz

χcc=-37.586 MHz

Extended Townes-Dailey analysis of the quadrupole tensor

χ0 = +2292.712 MHz, 127I, 5p electron. Gordy & Cooke has +292.71 MHz, a typo.

Xaa

0

0

0

Xbb

0

0

0

Xcc

na

X0

0

0

0

.5 X0

0

0

0

.5 X0

nb

.5 X0

0

0

0

X0

0

0

0

.5 X0

nc

.5 X0

0

0

0

.5 X0

0

0

0

X0

HSiI: na = 1.53, nb = 2.00, nc =1.75

{HGeBr: na = 1.58, nb = 2.00, nc = 1.80}