Interfacial Properties of Fluids Exhibiting Liquid Polyamorphism and Water-Like Anomalies

TL;DR

This paper investigates how molecular interconversion influences the interfacial properties of fluids with liquid polyamorphism and water-like anomalies, revealing complex behaviors like inflection points in surface tension and anomalous interfacial thickness.

Contribution

It introduces a microscopic model demonstrating the impact of interconversion on interfacial properties in fluids exhibiting polyamorphism and anomalies.

Findings

Surface tension shows inflection points or two extrema with temperature.

Interfacial thickness exhibits anomalous behavior.

Concentration profiles shift relative to density profiles.

Abstract

It has been hypothesized that liquid polyamorphism, the existence of multiple amorphous states in a single component substance, may be caused by molecular or supramolecular interconversion. A simple microscopic model [Caupin and Anisimov, Phys. Rev. Lett., 127, 185701, (2021)] introduces interconversion in a compressible binary lattice to generate various thermodynamic scenarios for fluids that exhibit liquid polyamorphism and/or water-like anomalies. Using this model, we demonstrate the dramatic effects of interconversion on the interfacial properties. In particular, we find that the liquid-vapor surface tension exhibits either an inflection point or two extrema in its temperature dependence. Correspondingly, we observe anomalous behavior of the interfacial thickness and a significant shift in the location of the concentration profile with respect to the location of the density profile.