An Ab-Initio Calculation of Raman Spectra of Binary Sodium Silicates

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2004,（4）
• 页码范围: 640-643
• 页数: 4页
• 语种: 英文

摘要

Raman spectra of binary sodium silicates are calculated by self-consistent field (SCF) molecular orbital ab initio calculation of the quantum chemical method with several poly silicon-oxygen tetrahedral model clusters when both the basis sets of 6-31 G and 6-31 G(d) are applied. The symmetric stretching vibrational frequency of non-bridging oxygen in a high frequency range and its Raman optical activity and scattering cross section are deduced and analysed. The correlation between this vibrational Raman shift and its microscopic environment of the silicon-oxygen tetrahedron is found based on interior stress of configuration, which depends on the connecting topology of adjacent silicon-oxygen tetrahedra (SiOT). A newly established empirical stress index of tetrahedron is introduced to elucidate the above relationship.