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arXiv · 2111.08109

Modeling Fluid Polyamorphism Through a Maximum-Valence Approach

Nikolay A. Shumovskyi·Thomas J. Longo·Sergey V. Buldyrev·Mikhail A. Anisimov
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Abstract

We suggest a simple model to describe polyamorphism in single-component fluids using a maximum-valence approach. The model contains three types of interactions: i) atoms attract each other by van der Waals forces that generate a liquid-gas transition at low pressures, ii) atoms may form covalent bonds that induce association, and iii) bonded atoms attract or repel each other stronger than non-bonded atoms, thus generating liquid-liquid separation. As an example, we qualitatively compare this model with the behavior of liquid sulfur and show that condition (iii) generates a liquid-liquid phase transition in addition to the liquid-gas phase transition.

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Nikolay A. Shumovskyi, Thomas J. Longo, Sergey V. Buldyrev, Mikhail A. Anisimov. 2021-11-15. Modeling Fluid Polyamorphism Through a Maximum-Valence Approach. https://doi.org/10.1103/physreve.106.015305

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