Wavenumbers and intensities of the fundamental vibrational modes of HNSi and DNSi from quantum-chemical computations

Abstract

By means of ab initio quantum-chemical computations with large basis sets and extensive treatment of electronic correlation effects, we have calculated the transition wavenumbers and absolute intensities of the fundamental vibrational modes of 1 H 14 N 28 Si and 2 H 14 N 28 Si and other molecular properties. The available experimental data were used to test the nature of the basis sets and the extent of correlation needed to reproduce the observed properties. General features of these computations are discussed in relation to the cancellation of errors due to the incomplete basis set with errors due to the incomplete treatment of electronic correlation.