Accurate simulation estimates of phase behaviour in ternary mixtures with prescribed composition

TL;DR

This paper introduces a Monte Carlo simulation method for accurately predicting phase behavior in ternary mixtures with fixed overall composition, useful for understanding complex fluid systems.

Contribution

It presents a novel isobaric semi-grand canonical ensemble Monte Carlo scheme that precisely estimates phase coexistence properties in ternary mixtures under realistic conditions.

Findings

Successfully tracks phase coexistence paths in a Lennard-Jones mixture.

Accurately estimates phase compositions and fractions.

Demonstrates applicability to complex fluid systems.

Abstract

This paper describes an isobaric semi-grand canonical ensemble Monte Carlo scheme for the accurate study of phase behaviour in ternary fluid mixtures under the experimentally relevant conditions of prescribed pressure, temperature and overall composition. It is shown how to tune the relative chemical potentials of the individual components to target some requisite overall composition and how, in regions of phase coexistence, to extract accurate estimates for the compositions and phase fractions of individual coexisting phases. The method is illustrated by tracking a path through the composition space of a model ternary Lennard-Jones mixture.