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Evaluation of phenomenological one-phase criteria for the melting and freezing of softly repulsive particles

Franz Saija·Santi Prestipino·Paolo V. Giaquinta
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Abstract

We test the validity of some widely used phenomenological criteria for the localization of the fluid-solid transition thresholds against the phase diagrams of particles interacting through the exp-6, inverse-power-law, and Gaussian potentials. We find that one-phase rules give, on the whole, reliable estimates of freezing/melting points. The agreement is ordinarily better for a face-centered-cubic solid than for a body-centered-cubic crystal, even more so in the presence of a pressure-driven re-entrant transition of the solid into a denser fluid phase, as found in the Gaussian-core model.

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Franz Saija, Santi Prestipino, Paolo V. Giaquinta. 2006-05-19. Evaluation of phenomenological one-phase criteria for the melting and freezing of softly repulsive particles. https://doi.org/10.1063/1.2208357

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