Hexatic phase in the two-dimensional Gaussian-core model

S. Prestipino; F. Saija; P. V. Giaquinta

doi:10.1103/physrevlett.106.235701

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arXiv · 1107.0828

Hexatic phase in the two-dimensional Gaussian-core model

S. Prestipino·F. Saija·P. V. Giaquinta

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Abstract

We present a Monte Carlo simulation study of the phase behavior of two-dimensional classical particles repelling each other through an isotropic Gaussian potential. As in the analogous three-dimensional case, a reentrant-melting transition occurs upon compression for not too high temperatures, along with a spectrum of water-like anomalies in the fluid phase. However, in two dimensions melting is a continuous two-stage transition, with an intermediate hexatic phase which becomes increasingly more definite as pressure grows. All available evidence supports the Kosterlitz-Thouless-Halperin-Nelson-Young scenario for this melting transition. We expect that such a phenomenology can be checked in confined monolayers of charge-stabilized colloids with a softened core.

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S. Prestipino, F. Saija, P. V. Giaquinta. 2011-07-05. Hexatic phase in the two-dimensional Gaussian-core model. https://doi.org/10.1103/physrevlett.106.235701

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