Theoretical study of the non-Arrhenius temperature dependence of thermal rate constants for the $H+H2S→H2+SH$ reaction Available to Purchase

Thermal rate constants for the $H+H2S→H2+SH$ reaction have been calculated over a temperature range of 100–2500 K using variational transition state theory combined with the multidimensional semiclassical tunneling correction. Potential energy curves for the reaction have been calculated using the spin-projected fourth-order Mo/ller–Plesset perturbation method and quadratic configuration–interaction method with the correlation-consistent polarized valence triple-ζ basis set. The calculated rate constants agree quite well with experiment over a wide range of temperature; in particular, excellent agreement with experiment is obtained around room temperatures. We have thus succeeded in quantitatively predicting the non-Arrhenius temperature dependence of thermal rate constants for the present reaction without adjusting any potential parameters, which has been observed recently by Yoshimura et al. [Chem. Phys. Lett. 189, 199 (1992)] and by Peng, Hu, and Marshall [J. Phys. Chem. 103, 5307 (1999)].