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arXiv · 1301.4021

Silica-Like Sequence of Anomalies in Core-Softened Systems

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

In this paper we present a simulation study of density, structural and diffusion anomalies in core-softened system introduced in our previous publications. It is well-known, that with appropriate parametrization, core-softened systems are remarkable model liquids that exhibit anomalous properties observed in tetrahedral liquids such as silica and water. It is widely believed that core-softened potentials demonstrate the water-like sequence of anomalies. We show that with increasing the depth of the attractive part of the potential the order of the region of anomalous diffusion and the regions of density and structural anomalies is inverted and have the silica-like sequence. We also show that the slope of the Widom line is negative like in water.

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Yu. D. Fomin, E. N. Tsiok, V. N. Ryzhov. 2013-01-17. Silica-Like Sequence of Anomalies in Core-Softened Systems. https://doi.org/10.1103/physreve.87.042122

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