Interaction and Photodissociation of Electronic Excited States of HS2 in the Ultraviolet Region: A Theoretical Contribution

HS2 molecules play an important role in the photochemical processes in combustion, atmosphere, and interstellar medium, yet our knowledge about the electronic excited states in the UV region is limited. In this study, we perform high-level ab initio calculations on electronic states of HS2 using the internally contracted multireference configuration interaction method including the Davidson correction (icMRCI + Q) method. The vertical transition energies, oscillator strengths, electron configurations, and transitions of thirteen electronic states of HS2 with energy up to 8 eV are calculated at the icMRCI + QJaug-cc-pv(5 + d)Z level. Based on the calculated potential energy curves, we investigate the interaction and photodissociation mechanism of the electronic states, which should shed some light on the decomposition processes of the gas-phase HS2 molecules in the ultraviolet region.