Toward a robust and general molecular simulation method for computing solid-liquid coexistence.

David M Eike; Joan F Brennecke; Edward J Maginn

doi:10.1063/1.1823371

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Toward a robust and general molecular simulation method for computing solid-liquid coexistence.

David M Eike·Joan F Brennecke·Edward J Maginn

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Abstract

A rigorous and generally applicable method for computing solid-liquid coexistence is presented. The method overcomes some of the technical difficulties associated with other solid-liquid simulation procedures and can be implemented within either a molecular dynamics or Monte Carlo framework. The method consists of three steps: First, relative Gibbs free energy curves are created for the solid and liquid phases using histogram reweighting. Next, the free energy difference between the solid and liquid phases is evaluated at a single state point by integrating along a pseudosupercritical transformation path that connects the two phases. Using this result, the solid and liquid free energy curves are referenced to a common point, allowing a single coexistence point to be determined. Finally, Gibbs-Duhem integration is used to determine the full coexistence curve. To evaluate its utility, this method is applied to the Lennard-Jones and NaCl systems. Results for solid-liquid coexistence agree with previous calculations for these systems. In addition, it is shown that the NaCl model does not correctly describe solid-liquid coexistence at high pressures. An analysis of the accuracy of the method indicates that the results are most sensitive to the transformation free energy calculation.

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Computer Simulation Models, Chemical Models, Molecular Molecular Conformation Phase Transition Sodium Chloride Solutions Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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David M Eike, Joan F Brennecke, Edward J Maginn. 2005-01-01. Toward a robust and general molecular simulation method for computing solid-liquid coexistence.. https://doi.org/10.1063/1.1823371

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