Enhanced Sampling of Configuration and Path Space in a Generalized Ensemble by Shooting Point Exchange

TL;DR

This paper introduces a novel simulation method that combines transition path sampling with enhanced configuration space exploration, improving efficiency in studying rare molecular events without altering their natural dynamics.

Contribution

It presents a new exchange move technique between configuration and trajectory space within a generalized ensemble, enabling better sampling of complex molecular transitions.

Findings

Enhanced sampling efficiency for systems with multiple transition channels

Provides thermodynamic, kinetic, and reaction coordinate information

Demonstrated on proline isomerization in a tetrapeptide

Abstract

The computer simulation of many molecular processes is complicated by long time scales caused by rare transitions between long-lived states. Here, we propose a new approach to simulate such rare events, which combines transition path sampling with enhanced exploration of configuration space. The method relies on exchange moves between configuration and trajectory space, carried out based on a generalized ensemble. This scheme substantially enhances the efficiency of the transition path sampling simulations, particularly for systems with multiple transition channels, and yields information on thermodynamics, kinetics and reaction coordinates of molecular processes without distorting their dynamics. The method is illustrated using the isomerization of proline in the KPTP tetrapeptide.