A Novel Path Sampling Method for the Calculation of Rate Constants

TL;DR

This paper introduces a new, more efficient path sampling method for calculating rate constants of transitions over high free energy barriers, demonstrated on molecular isomerization.

Contribution

A novel transition path sampling scheme that measures fluxes through multiple interfaces simultaneously, doubling efficiency over existing methods.

Findings

At least twice as efficient as previous algorithms.

Successfully applied to diatomic molecule isomerization.

Provides a practical approach for complex transition rate calculations.

Abstract

We derive a novel efficient scheme to measure the rate constant of transitions between stable states separated by high free energy barriers in a complex environment within the framework of transition path sampling. The method is based on directly and simultaneously measuring the fluxes through many phase space interfaces and increases the efficiency with at least a factor of two with respect to existing transition path sampling rate constant algorithms. The new algorithm is illustrated on the isomerization of a diatomic molecule immersed in a simple fluid.