Direct Evaluation of Multi-Component Phase Equilibria Using Flat-Histogram Methods

Published

October 1, 2005

Author(s)

Jeffrey R. Errington, Vincent K. Shen

Abstract

We present a method for directly locating density-driven phase transitions in multi-component systems. Phase coexistence conditions are determined through manipulation of a total density probability distribution evaluated over a density range that includes both coexisting phases. Saturation quantities are determined through appropriate averaging of density-dependent mean values of a given property of interest. We discuss how to implement the method in both the grand canonical and isothermal-isobaric semigrand ensembles. Calculations can be conducted using any of the recently-introduced flat histogram techniques. Here, we combine the general algorithm with a transition-matrix approach to produce an efficient self-adaptive technique for determining multi-component phase equilibrium properties. To assess the performance of the new method, we generate phase diagrams for a number of binary and ternary Lennard-Jones mixtures.

Citation

Journal of Chemical Physics

Volume

123

Pub Type

Journals

Keywords

molecular simulation, monte carlo, phase equilibria, statistical mechanics

Citation

Errington, J. and Shen, V. (2005), Direct Evaluation of Multi-Component Phase Equilibria Using Flat-Histogram Methods, Journal of Chemical Physics (Accessed October 9, 2025)