Microwave spectroscopy of the heavy-atom carbene analog HSiI and DSiI Lu Kang Southern Polytechnic State University Marietta, GA Mohammed A. Gharaibeh and Dennis J. Clouthier University of Kentucky, Lexington, KY Stewart E. Novick Wesleyan 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’s MBER (originally Norman Ramsey’s)

H 3 SiI in a methanol/dry ice bath held between -40 and -50 C, P ~ 5 torr 5 torr H 3 SiI in 2 atm of Ne, discharge of V immediately following supersonic expansion to produce HSiI (or DSiI if we start with D 3 SiI)

2/3 Spectroscopic constants of HSiI as measured by FTMW spectroscopy

The r 0 structure of HSiI A o A

This workClouthier et al a r 0 (H – Si)1.5405(16) Å1.534(1) Å r 0 (Si – I) (9) Å2.463(1) Å θ 0 (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 95 o 95.3 o 94.1 o 92.7 o (X bb -X cc ) X aa e e 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, (2009) d. This work e. B3LYP/aug-cc-pvqz

b a c χ aa = MHz χ bb = MHz χ cc = MHz Extended Townes-Dailey analysis of the quadrupole tensor χ 0 = MHz, 127 I, 5p electron. Gordy & Cooke has MHz, a typo. HSiI: n a = 1.53, n b = 2.00, n c =1.75 {HGeBr: n a = 1.58, n b = 2.00, n c = 1.80}