Structural properties of the Jagla fluid

TL;DR

This study investigates the structural properties of the Jagla fluid using Monte Carlo simulations, integral equations, and the RFA method, providing insights into its radial distribution function and phase behavior.

Contribution

The paper introduces a semi-analytical RFA method for Jagla fluid, validated against simulations, and explores its asymptotic behavior and phase transition lines.

Findings

Good agreement between RFA predictions and simulations for $g(r)$

RFA effectively describes asymptotic decay of correlations

Predicted Fisher--Widom and Widom lines for the Jagla fluid

Abstract

The structural properties of the Jagla fluid are studied by Monte Carlo (MC) simulations, numerical solutions of integral equation theories, and the (semi-analytical) rational-function approximation (RFA) method. In the latter case, the results are obtained from the assumption (supported by our MC simulations) that the Jagla potential and a potential with a hard core plus an appropriate piecewise constant function lead to practically the same cavity function. The predictions obtained for the radial distribution function, $g(r)$, from this approach are compared against MC simulations and integral equations for the Jagla model, and also for the limiting cases of the triangle-well potential and the ramp potential, with a general good agreement. The analytical form of the RFA in Laplace space allows us to describe the asymptotic behavior of $g(r)$ in a clean way and compare it with MC simulations for representative states with oscillatory or monotonic decay. The RFA predictions for the Fisher--Widom and Widom lines of the Jagla fluid are obtained.