Minimal Microscopic Model for Liquid Polyamorphism and Waterlike Anomalies

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 noninterconverting 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 waterlike anomalies.

Automated summary

Liquid polyamorphism refers to the ability of a single-component substance to exist in multiple liquid phases. A minimal model has been proposed to explain this phenomenon using a binary lattice model, providing unprecedented insights into the phase behaviors of interconverting fluids. This model offers a unified theoretical framework to describe supercooled water and other polyamorphic liquids with waterlike anomalies.