Spectroscopic and structural features of small thiocarbonyl molecules in low-lying excited states: further applications of a variant of the orthogonal gradient method

Abstract

Structural parameters of a set of five thiocarbonyl molecules in the lowest nπ^∗ states are calculated by using a generalized orbital optimization algorithm (a variant of the orthogonal gradient method) in an INDO MCSCF framework. Transition energies, singlet-triplet splittings, planar inversion barriers, and dipole moments in nπ^∗ states of different spin multiplicities are reported. Predicted structural features agree reasonably well with available experimental or theoretical data. Some interesting trends are noted in the computed inversion barrier heights, singlet-triplet splittings, and dipole moments in nπ^∗ states.