A quantitative study of non-Condon effects in the S2O C̃→X̃ emission spectrum

A novel technique has been developed for the quantitative study of vibronically-resolved transition intensities in polyatomic molecules beyond the Condon approximation. Matrix elements of coordinate-dependent transition moment operators are evaluated analytically with the pertinent vibrational wave functions obtained by means of Lie algebraic methods. Experimentally-observed S2O C̃ 1A′–X̃ 1A′(π*−π) emission intensities, in conjunction with previous Franck–Condon calculations, reveal pronounced non-Condon effects for vibronic bands terminating on higher-lying vibrational levels of the ground electronic state. The transitiondipole moment is examined as a function of both the S–O and S–S local stretching coordinates