Structural and thermodynamic properties of fluids whose molecules interact via one-, two-, and three-step potentials

TL;DR

This paper investigates the structural and thermodynamic properties of complex fluids with multi-step interaction potentials using a semi-analytical approximation, validated against simulation data.

Contribution

It introduces a semi-analytical rational-function approximation method for fluids with multi-step potentials, extending previous formulations and confirming accuracy through simulations.

Findings

The method accurately predicts structural properties.

Thermodynamic properties match simulation results.

Applicable to potentials with multiple constant sections.

Abstract

The structural and thermodynamic properties of fluids whose molecules interact via potentials with a hard-core plus a square well, a square shoulder, and a second square well, are considered. Those properties are derived by using a (semi-analytical) rational-function approximation method as a particular case of the more general formulation provided earlier involving potentials with a hard-core plus $n$ piecewise constant sections. Comparison of the results with recent simulation data confirms the usefulness of the approach.