High-dimensional ab initio potential energy surfaces for reaction dynamics calculations

Abstract

There has been great progress in the development of potential energy surfaces (PESs) for reaction dynamics that are fits to ab initio energies. The fitting techniques described here explicitly represent the invariance of the PES with respect to all permutations of like atoms. A review of a subset of dynamics calculations using such PESs (currently 16 such PESs exist) is then given. Bimolecular reactions of current interest to the community, namely, H + CH₄ and F + CH₄, are focused on. Unimolecular reactions are then reviewed, with a focus on the photodissociation dynamics of H₂CO and CH₃CHO, where so-called “roaming” pathways have been discovered. The challenges for electronically non-adiabatic reactions, and associated PESs, are presented with a focus on the OH* + H₂ reaction. Finally, some thoughts on future directions and challenges are given.