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arXiv · 1401.0679

Inverse melting in a two-dimensional off-lattice model

Ahmad M. Almudallal·Sergey V. Buldyrev·Ivan Saika-Voivod
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Abstract

We carry out computer simulations of a simple, two-dimensional off-lattice model that exhibits inverse melting. The monodisperse system comprises core-softened disks interacting through a repulsive square shoulder located inside an attractive square well. By systematically varying the potential parameters, we increase the pressure range over which the liquid freezes to a crystal upon isobaric heating. The effect is largely controlled by the extent of the shoulder. Despite occurring in two dimensions, the melting transition is first order and to a liquid, rather than to a hexatic or quasicrystal phase. We also provide comment on a commonly employed correlation function used to determine the degree of translational ordering in a system.

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Ahmad M. Almudallal, Sergey V. Buldyrev, Ivan Saika-Voivod. 2014-01-03. Inverse melting in a two-dimensional off-lattice model. https://doi.org/10.1063/1.4870086

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