Connecting thermodynamic and dynamical anomalies of water-like liquid-liquid phase transition in the Fermi-Jagla model

TL;DR

This study uses molecular dynamics simulations of the Fermi-Jagla model to explore water-like liquid-liquid phase transitions and associated thermodynamic and dynamic anomalies, revealing interconnected hierarchical structures.

Contribution

It demonstrates the connection between thermodynamic and dynamic anomalies in the Fermi-Jagla model near the liquid-liquid critical point, highlighting the hierarchical structure of anomalies.

Findings

Density, diffusion, viscosity, and entropy anomalies are characterized.

Anomalies follow Rosenfeld's scaling relationship.

Thermodynamic and dynamic anomalies form nested hierarchical structures.

Abstract

We present a study using molecular dynamics simulations based on the Fermi-Jagla potential model, which is the continuous version of the mono-atomic core-softened Jagla model [J. Y. Abraham, S. V. Buldyrev, and N. Giovambattista, J. Phys. Chem. B, 115, 14229 (2011)]. This model shows the water-like liquid-liquid phase transition between high-density and low-density liquids at the liquid-liquid critical point. In particular, the slope of the coexistence line becomes weakly negative, which is expected to represent one of anomalies of liquid polyamorphism. In this study, we examined the density, dynamic, and thermodynamic anomalies in the vicinity of the liquid-liquid critical point. The boundaries of density, self-diffusion, shear viscosity, and excess entropy anomalies were characterized. Furthermore, these anomalies are connected according to the Rosenfeld's scaling relationship between the excess entropy and the transport coefficients such as diffusion and viscosity. The results demonstrate the hierarchical and nested structures regarding the thermodynamic and dynamic anomalies of the Fermi-Jagla model.