Theoretical investigation of the dissociation of OCS2+ in the process OCS(X 1Σ+) + hv → OCS2+ → CO+ (X2Σ+) + S+ (4S)

Abstract Ab initio calculations of the potential energy surface of the X 3 Σ − state of OCS 2+ have been performed. A high and wide potential barrier is found for the dissociation into CO + (X 2 Σ + ) +S + ( 4 S). It appears that it is very unlikely that the system gets through this barrier when it is obtained from the ground state of OCS. In addition, a semi-quantitative correlation diagram between the lowest electronic states of OCS 2+ and of CO + +S + is proposed. It appears on this diagram that the A 3 Σ − state might lead to the ground state fragments via two successive non-adiabatic transitions.