Studying Rare Events using Forward-Flux Sampling: Recent Breakthroughs and Future Outlook

TL;DR

This paper reviews recent advances and future prospects of forward-flux sampling, a computational technique for studying rare events crucial in biological and material systems, highlighting its methodological developments and diverse applications.

Contribution

It provides a comprehensive overview of recent methodological variants of forward-flux sampling and discusses its applications and future directions in rare event studies.

Findings

Recent methodological extensions of forward-flux sampling are summarized.

Applications span biological and material science systems.

Potential future research avenues are outlined.

Abstract

Rare events are processes that occur upon the emergence of unlikely fluctuations. Unlike what their name suggests, rare events are fairly ubiquitous in nature, as the occurrence of many structural transformations in biology and material sciences is predicated upon crossing large free energy barriers. Probing the kinetics and uncovering the molecular mechanisms of possible barrier crossings in a system is critical to predicting and controlling its structural and functional properties. Due to their activated nature, however, rare events are exceptionally difficult to study using conventional experimental and computational techniques. In recent decades, a wide variety of specialized computational techniques-- known as advanced sampling techniques-- have been developed to systematically capture improbable fluctuations relevant to rare events. In this perspective, we focus on a technique called forward flux sampling (Allen~\emph{et al.,}~\emph{J. Chem. Phys.}, {\bf 124}: 024102, 2006), and overview its recent methodological variants and extensions. We also provide a detailed overview of its application to study a wide variety of rare events, and map out potential avenues for further explorations.