Extending and validating bubble nucleation rate predictions in a Lennard-Jones fluid with enhanced sampling methods and transition state theory

TL;DR

This paper presents a validated computational approach combining free energy methods, transition state theory, and recrossing corrections to accurately predict bubble nucleation rates in a Lennard-Jones fluid across various regimes, bridging different literature methods.

Contribution

It introduces a robust, generic recipe for calculating nucleation rates that aligns with classical methods and challenges some existing simulation outliers.

Findings

Rate predictions agree with classical nucleation theory and seeding methods.

Forward flux sampling rates are identified as outliers.

The approach is validated across multiple superheated and cavitation regimes.

Abstract

We calculate bubble nucleation rates in a Lennard-Jones fluid through explicit molecular dynamics simulations. Our approach -- based on a recent free energy method (dubbed reweighted Jarzynski sampling), transition state theory, and a simple recrossing correction -- allows us to probe a fairly wide range of rates in several superheated and cavitation regimes in a consistent manner. Rate predictions from this approach bridge disparate independent literature studies on the same model system. As such, we find that rate predictions based on classical nucleation theory, direct brute force molecular dynamics simulations, and seeding are consistent with our approach and one another. Published rates derived from forward flux sampling simulations are, however, found to be outliers. This study serves two purposes. First, we validate the reliability of common modeling techniques and extrapolation approaches on a paradigmatic problem in materials science and chemical physics. Second, we further test our highly generic recipe for rate calculations, and establish its applicability to nucleation processes.