Time-dependent Wave Packet Quantum Scattering Study of Reaction S(³P)+H₂→HS+H on a New ab initio Potential Energy Surface ³A'

A new potential energy surface is presented for the triplet state ³A' of the chemical reaction S(³P)+H₂ from a set of accurate ab initio data. The single point energies are computed using highly correlated complete active space self-consistent-field and multi-reference config-uration interaction wave functions with a basis set of aug-cc-pV5Z. We have fitted the full set of energy values using many-body expansion method with an Aguado-Paniagua function. Based on the new potential energy surface, we carry out the time-dependent wave packet scattering calculations over the collision energy range of 0.8～2.2 eV. Both the centrifugal-sudden approximation and Coriolis Coupling cross sections are obtained. In addition, the total reaction probabilities are calculated for the reactant H₂ initially in the vibrational states v=0～3 (j=0). It is found that initial vibrational excitation enhances the title reaction.