Accurate theoretical predictions on the mechanisms of OSiS formation and its dissociation channels

International audienceMultireference configuration interaction calculations are performed to investigate the potential energy surface of the S+SiO and O+SiS reactions, which are of astrochemical relevance. Several singlet and triplet electronic states are calculated in order to explore the reaction paths. It is shown that although collisions with ground-state reactants do not lead to the OSiS molecule adiabatically, the probabilities for such a spin-forbidden process are high. It is also predicted that SiS is easily converted to SiO. Spin orbit couplings and other properties are also calculated and several electronic states are explored