15min:
A HIGH-RESOLUTION STUDY OF THE FOUR LOWEST FUNDAMENTAL BANDS AND ACCURATE DETERMINATION OF THE GROUND STATE CONSTANTS OF H3Si37Cl.

G. GRANER, S. BOSC, Y. HENNEQUIN, Laboratoire de Physique Moléculaire et Applications, CNRS, Bât. 350, Campus d'Orsay, F-91405 Orsay Cédex, France; H. BÜRGER AND S. BAILLEUX, Anorganische Chemie, FB 9, Universität-Gesamthochschule, D-42097 Wuppertal, Germany.

In order to determine the structure and force field of silyl chloride, the infrared spectra of several isotopomers were studied. After monoisotopic D3Si35Cl (previous communication), we report here on the analysis of the monoisotopic H3Si37Cl species. Here too, the two fundamental bands nu3 (543.968cm-1) and nu6 (663.736 cm-1) are linked by a Coriolis resonance but its effects are less important than for D3SiCl and especially than for the two nearly degenerate fundamental bands nu2 (947.982 cm-1) and nu5 (950.657 cm-1). The 'normal' ground state constants B0, DJ0, DJK0, HJ0, HJK0, and DKJ0 were deduced from more than 6000 GSCD. As for the constants A0 and DK0, they were obtained by the same method as for D3Si35Cl. Calibration errors were detected and corrected by checking the closed loop between nu6, (2nu6)0 and (2nu6)0 - nu6. The values obtained are A0 = 2.84564 cm-1 and DK0 = 2.54 × 10-6 cm-1 (provisional values). Upper state energies were also determined for nu3, nu6, nu2, nu5, (2nu6)\pm2, (2nu6)0, 2nu3, and nu3 + nu6. Some interesting features of the hot bands nu3 + nu6 - nu3 and nu3 + nu6 - nu6 will also be reported.