Millimeter-wave and high-resolution FTIR spectroscopy of : the ground and states

✍ Scribed by J.-F. D’Eu; J. Demaison; H. Bürger

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 199 KB
• Volume: 218
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1016/s0022-2852(02)00008-5

✦ Synopsis

The first high-resolution infrared spectroscopic study of the m 4 band at 322:85 cm À1 of SiH 2 F 2 is reported, and millimeter-wave spectra in the 350-471 GHz range of the ground and the v 4 ¼ 1 excited states are presented. These data have been combined with existing microwave measurements and substantially improved ground state parameters, and molecular constants of the v 4 ¼ 1 state, have been determined. The quadratic, cubic, and semidiagonal quartic force field of difluorosilane has been calculated at the MP2 level of theory employing a basis set of polarized valence triple-zeta quality. The spectroscopic constants derived from the force field are in excellent agreement with experiment. The equilibrium structure has been derived from experimental ground state rotational constants and ab initio rovibrational interaction parameters. This semiexperimental structure is in perfect agreement with the ab initio equilibrium geometry calculated at the CCSD(T) level of theory.