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arXiv · 1412.7192

New density functional approach for solid-liquid-vapor transitions in pure materials

Gabriel Kocher·Nikolas Provatas
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Abstract

A new phase field crystal (PFC) type theory is presented, which accounts for the full spectrum of solid-liquid-vapor phase transitions within the framework of a single density order parameter. Its equilibrium properties show the most quantitative features to date in PFC modelling of pure substances, and full consistency with thermodynamics in pressure-volume-temperature space is demonstrated. A method to control either the volume or the pressure of the system is also introduced. Non-equilibrium simulations show that 2 and 3-phase growth of solid, vapor and liquid can be achieved, while our formalism also allows for a full range of pressure-induced transformations. This model opens up a new window for the study of pressure driven interactions of condensed phases with vapor, an experimentally relevant paradigm previously missing from phase field crystal theories.

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Gabriel Kocher, Nikolas Provatas. 2015-02-27. New density functional approach for solid-liquid-vapor transitions in pure materials. https://doi.org/10.1103/physrevlett.114.155501

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