Metashooting: A Novel Tool for Free Energy Reconstruction from Polymorphic Phase Transition Mechanisms

TL;DR

Metashooting is a new computational scheme that combines transition path sampling and metadynamics to analyze solid-solid phase transitions, providing detailed free energy landscapes and mechanistic insights.

Contribution

This paper introduces metashooting, a novel method integrating transition path sampling and metadynamics for comprehensive free energy and mechanistic analysis of phase transitions.

Findings

Successfully applied to ZnO phase transition

Revealed intermediate configurations and mechanistic regimes

Achieved higher accuracy in free energy mapping

Abstract

We introduce a novel scheme for the mechanistic investigation of solid-solid phase transitions, which we dub \textit{metashooting}. Combining transition path sampling molecular dynamics and metadynamics, this scheme allows for both a complete mechanistic analysis and a detailed mapping of the free energy surface. This is illustrated by performing \textit{metashooting} calculations on the pressure-induced B4/B3 $\rightarrow$ B1 phase transition in ZnO. The resulting free energy map helps to clarify the role of intermediate configurations along this activated process and the competition between different mechanistic regimes with superior accuracy. We argue that \textit{metashooting} can be efficiently applied to a broader class of activated processes