Theoretical study on the reaction of the ground state 1Σ + of YS + with oxygen-transfer reagent: YS ++COS→YO ++CS 2 in the gas phase

Abstract

The reaction mechanisms of the ground state 1Σ + of YS + with oxygen-transfer reagent: YS ++COS→YO ++CS 2 in the gas phase has been studied by ab initio methods. It is found that the reaction proceeds via two four-center transition states (TS1 and TS2) with a cyclic complex ( b) locating between them on the reaction potential surface. The activation barriers of the two transition state are both negatively valued by −7.6 kcal/mol at MP4 (SDTQ)/6-31+G*//MP2/6-31+G* level plus ZPE relative to the reactants. The collision rate coefficient of the reactants should be the main factor limiting the reaction rate. The similarities and differences between YS + and ScS + for this type reaction were also discussed.