A Skew Dividing Surface for Accurate Nonadiabatic Mean-Field Ring Polymer Rates

TL;DR

This paper introduces a novel skew dividing surface and reaction coordinate for MF-RPMD, improving the accuracy of nonadiabatic reaction rate calculations by effectively sampling kinked electronic configurations.

Contribution

It develops a new skew dividing surface and electronic state-based reaction coordinate that enhances MF-RPMD's accuracy for nonadiabatic rate simulations.

Findings

Accurately computes nonadiabatic reaction rates for model systems.

Demonstrates improved sampling of kinked electronic configurations.

Validates the method's effectiveness through numerical results.

Abstract

Mean-Field Ring Polymer Molecular Dynamics (MF-RPMD) is a powerful, efficient, and accurate method for approximate quantum dynamic simulations of multi-level system dynamics. Initial efforts to compute nonadiabatic reaction rates using MF-RPMD were not successful; recent work showed that this can be remedied by including a simple, if adhoc, correction term that accounts for the formation of `kinked' or mixed electronic state ring polymer configurations. Here, we build on this idea, introducing a electronic state population based reaction coordinate and novel skew dividing surface that constrains nuclear positions to configurations where the reactant and product state potentials are near-degenerate and that samples kinked electronic state configurations. We then demonstrate the numerical accuracy of this method in computing rates for a series of nonadiabatic model systems.