Reactions dynamics for X + H2 insertion reactions(X=C(1D), N(2D), O(1D), S(1D)) with Cayley Propagator ring-polymer molecular dynamics

Abstract: In this work, rate coefficients of four prototypical insertion reactions, X + H2 -- H + XH (X=C(1D), N(2D), O(1D), S(1D)) and associated isotope reactions are calculated based on ring polymer molecular dynamics (RPMD) with Cayley propagator (Cayley-RPMD). The associated kinetic isotope effects (KIEs) are systematically studied too. The Cayley propagator used in this work increases the stability of numerical integration in RPMD calculations, and also supports a larger evolution time interval, allowing us to reach both high accuracy and efficiency. So, our results do not only provide chemical kinetic data for the title reactions in an extended temperature range, but also consist of experimental results, standard RPMD, and other theoretical methods. The results in this work also reflect that Cayley-RPMD has strong consistency and high reliability in the investigations of chemical dynamics for insertion reactions.