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arXiv · 1911.06086

Melting scenarios of two-dimensional Hertzian spheres with a single triangular lattice

E. N. Tsiok·E. A. Gaidukm Yu. D. Fomin·V. N. Ryzhov
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Abstract

We present a molecular dynamics simulation study of the phase diagram and melting scenarios of two-dimensional Hertzian spheres with exponent 7/2. We have found multiple re-entrant melting of a single crystal with a triangular lattice in a wide range of densities from 0.5 to 10.0. Depending on the position on the phase diagram, the triangular crystal has been shown to melt through both two-stage melting with a first-order hexatic - isotropic liquid transition and a continuous solid - hexatic transition as well as in accordance with the Berezinskii-Kosterlitz-Thouless-Halperin-Nelson-Young (BKTHNY) scenario (two continuous transitions with an intermediate hexatic phase). We studied the behavior of heat capacity and have shown that despite two-stage melting, the heat capacity has one peak which seems to correspond to a solid-hexatic transition.

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E. N. Tsiok, E. A. Gaidukm Yu. D. Fomin, V. N. Ryzhov. 2019-11-14. Melting scenarios of two-dimensional Hertzian spheres with a single triangular lattice. https://arxiv.org/abs/1911.06086

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