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arXiv · 2104.08117

Minimal microscopic model for liquid polyamorphism and water-like anomalies

Abstract

Liquid polyamorphism is the intriguing possibility for a single component substance to exist in multiple liquid phases. We propose a minimal model for this phenomenon. Starting with a binary lattice model with critical azeotropy and liquid-liquid demixing, we allow interconversion of the two species, turning the system into a single-component fluid with two states differing in energy and entropy. Unveiling the phase diagram of the non-interconverting binary mixture gives unprecedented insight on the phase behaviors accessible to the interconverting fluid, such as a liquid-liquid transition with a critical point, or a singularity-free scenario, exhibiting thermodynamic anomalies without polyamorphism. The model provides a unified theoretical framework to describe supercooled water and a variety of polyamorphic liquids with water-like anomalies.

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BibTeXRIS

Frédéric Caupin, Mikhaïl A. Anisimov. 2021-04-16. Minimal microscopic model for liquid polyamorphism and water-like anomalies. https://doi.org/10.1103/physrevlett.127.185701

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