Infrared intensities of ν3 and ν4 in SiH4, GeH4 and SnH4
1994; Elsevier BV; Volume: 320; Linguagem: Inglês
10.1016/0022-2860(94)07974-9
ISSN1872-8014
AutoresAlison M. Coats, D.C. McKean, D. Steele,
Tópico(s)Molecular Spectroscopy and Structure
ResumoNew infrared intensity data for the bands owing to ν3 and ν4 in SiH4, GeH4 and SnH4 are reported. Substantial changes from earlier estimates are found, particularly for SnH4. The intensities in SiH4 are also calculated ab initio using 6–31G* and 6–31G** basis sets. With the signs of ∂p/∂Q fixed by these and prior calculations, ∂p/∂S values are calculated and interpreted in terms of zero order electro optical parameters, charge fluxes and atomic polar tensors. The atom polarisation PA found for SiH4 agrees well with that from refractive index and dielectric constant measurements. The infrared intensities found correlate well with the frequency shifts from gas to high temperature crystal phase. The Haas-Ketelaar equation accounts for 45% and 70% respectively of these shifts in ν3 and ν4, after appropriate estimates of density and refractive index have been made.
Referência(s)