Full-Dimensional Quantum Reaction Rate Calculations for H + CH4 → H2 + CH3 on a Recent Potential Energy Surface

Abstract

The thermal rate constant of the H + CH(4) → H(2) + CH(3) reaction on the recent potential energy surface (PES) of Corchado et al (CBE) (Corchado, J. C.; Bravo, J. L.; Espinosa-Garcia, J. J. Chem. Phys. 2009, 130, 184314) is computed employing the state-averaged multiconfigurational time-dependent Hartree approach in the temperature range 250-500 K. The CBE PES is global and is based on an analytic functional form that is fast to evaluate. This surface is therefore potentially useful for testing new quantum dynamics methods, and reference rate constants for this purpose are presented here. The thermal rate constants obtained are compared to results previously obtained on an accurate PES particularly designed for thermal rate constant calculations (Wu, T.; Werner, H.; Manthe, U. Science 2004, 306, 2227). The two sets of rate constants are found to agree almost perfectly.