Kinetic and dynamic studies of the H3+ + CO → H2 + HCO+/HOC+ reaction on a high-level <i>ab initio</i> potential energy surface

Abstract

The proton transfer reaction H3+ + CO → H2 + HCO+/HOC+ is of great importance in interstellar and circumstellar environments. The dynamics and kinetics of the reaction were studied using the quasiclassical trajectory approach on a newly developed ab initio potential energy surface (PES) for the ground electronic state. The PES was constructed by fitting 46 462 ab initio points at the level of CCSD(T)-F12a/aug-cc-pVTZ using the fundamental invariant-neural network method. The calculated product branching ratio, scattering angular distribution, and thermal rate coefficient agreed reasonably well with the experimental measurements, which were rationalized by the underlying reaction mechanisms.