High-Resolution FTIR Study of Thiocarbonyl Difluoride SCF2.

High-resolution ( approximately 3 x 10(-3) cm-1) FTIR spectra of the planar SCF2 molecule have been recorded in the range of the four lowest-lying fundamentals nu2 (789.535 cm-1), nu3 (526.697 cm-1), nu5 (419.546 cm-1), and nu6 (623.187 cm-1). For each band 4500-7500 transitions have been assigned and fitted to a standard Watson-type Hamiltonian up to quartic terms, sigma(Fit) approximately 3.5 x 10(-4) cm-1. No indication of rovibrational perturbations was found, excited state rotational and centrifugal distortion constants being close to their ground state values. Ground state parameters previously determined from microwave spectra were, in part, improved by a merge of the appropriately weighted microwave data and approximately 10 000 ground state combination differences that were obtained from the nu4 band and spanning J and Ka values of 88 and 49, respectively. Copyright 1998 Academic Press.