A theoretical study on S-loss photodissociation of the CS2+ ion

The CASPT2 potential energy curves for S-loss dissociation from the X2Πg, A2Πu, B2Σu+, C2Σg+, 14Σ−, 14Π, 12Σ−, and 24Σ− states of the CS2+ ion were calculated. A conical intersection point between the B2Σu+ and C2Σg+ potential energy surfaces was found. At the CASSCF level we located the minimum energy crossing points (MECPs) for the X2Πg/14Σ−, A2Πu/14Σ−, B2Σu+/14Σ−, C2Σg+/14Σ−, A2Πu/12Σ−, and B2Σu+/12Σ− state-pairs and calculated spin-orbit coupling values. MECP for the C2Σg+/12Σ− state-pair was not found. We suggest photodissociation processes via A2Πu and B2Σu+. Photodissociation mechanisms via A2Πu, B2Σu+, and C2Σg+ proposed in the previous experimental studies are discussed.

Graphical abstractA theoretical study on photodissociation of the CS2+ ion using multiconfiguration second-order perturbation theory.Download full-size image