Theoretical study on reaction mechanism and kinetics of HNCS with CN
Cuihong Sun1, Ying Liu, Baoen Xu
1Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
Abstract:
We presented a theoretical study on the detailed reaction mechanism and kinetics of the CN radical with the HNCS molecule. The barrierless minimum energy path and the most favorable entrance channel have been determined by constructing a two-dimensional potential energy surface of the C atom of CN attacking the HNCS molecule. The reaction of the C atom attacking the S atom was finally identified as the dominant entrance channel based on the rate constants' results calculated with the canonical variational transition state theory. The master equation method was employed to calculate the products' branching ratios, the overall rate constant, and the pressure dependence of the title reaction. The B3LYP∕6-311+G(2d,p) method was employed for all the geometrical optimizations and a multi-level extrapolation method based on the CCSD(T) and MP2(FC) energies was employed for further energy refinements.
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