Absorption and resonance emission spectra of SO2((X)over-tilde1A1/(C)over-tilde1B2) calculated from ab initio potential energy and transition dipole moment surfaces

We report here an analytical fit of the transition dipole moments between (X) over tilde (1)A(1) and (C) over tilde B-1(2) electronic states of SO2 calculated using a high level ab initio method. The absorption spectrum as well as the resonance emission spectra from several low-lying (C) over tilde B-1(2) vibrational levels are calculated using a newly developed ab initio potential energy surface (PES) and the transition dipole functions. The calculated spectra are in semi-quantitative agreement with available experimental data. A strong non-Condon effect is found for the emission spectra. (C) 2000 Elsevier Science B.V. All rights reserved.