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arXiv · 1804.04386

Note: Melting criterion for soft particle systems in two dimensions

Sergey Khrapak
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Abstract

A simple criterion for melting of two-dimensional crystals with soft long-ranged interactions is proposed. It states that the ratio of the transverse sound velocity of an ideal crystalline lattice to the thermal velocity is a quasi-universal number close to $4.3$ at melting. This criterion is arrived by reference to the Berezinskii-Kosterlitz-Thouless-Halperin-Nelson-Young theory of two-dimensional melting, combined with the observation that the ratio of transverse-to-longitudinal sound velocities is small in the soft interaction limit. Application of this criteria allows estimating melting lines in a simple yet relatively accurate manner. Two-dimensional weakly screened Yukawa systems represent one relevant example considered.

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Sergey Khrapak. 2018-04-12. Note: Melting criterion for soft particle systems in two dimensions. https://doi.org/10.1063/1.5027201

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