A general harmonic force field for methyl silane

✍ Scribed by J.L. Duncan; A.M. Ferguson

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 346 KB
• Volume: 52
• Category: Article
• ISSN: 1386-1425
• DOI: 10.1016/0584-8539(96)01687-x

✦ Synopsis

The number of accumulated spectroscopic data sensitive to the harmonic force constants of methyl silane has been augmented recently through high resolution infrared gas-phase studies of t2CH3SiH3, ~3CH3SiH 3 and tZCH3SiD3 species (J.L. Duncan, A.M. Ferguson and D.C. McKean, J. Mol. Spectrosc, 168 (1994) 522). This permits the determination of an empirical harmonic force field, in which 24 A~ and E species force constants out of the total of 36 are independently defined in terms of 72 data across five isotopic species. The empirical constants are compared with those from a scaled ab initio force field using a basis set of double zeta plus polarization quality, where very good agreement is found throughout. Ultimately, a best estimate general harmonic force field is presented in which the 12 undermined and numerically small interaction force constants are constrained to their ab initio predicted scaled values.