Direct evaluation of the physical characteristics of Yukawa fluids based on a simple approximation for the radial distribution function

• Published in: Results in physics 2020-12, Vol.19, p.103359, Article 103359
• Main Authors: Fairushin, I.I., Khrapak, S.A., Mokshin, A.V.
• Format: Article
• Language: English
• Subjects: Dispersion law of the longitudinal collective mode; Radial distribution function; Thermodynamic properties; Two-step approximation; Yukawa fluid
• ISSN: 2211-3797; 2211-3797
• DOI: 10.1016/j.rinp.2020.103359

•A simple approximation for the radial distribution (RDF) function is proposed.•The new approximation for the RDF yields thermodynamic quantities of Yukawa fluid.•Energy, pressure, and the dispersion laws are in agreement with MD simulation results. We propose a simple analytical approximation for the radial distribution function (RDF) in a single-component Yukawa fluid. The proposed RDF depends on the two input parameters – the non-ideality parameter Γ and the structure (screening) parameter κ, which determine the thermodynamic state of Yukawa systems. We demonstrate that various physical properties can be directly calculated using the proposed RDF. In particular, the internal energy and pressure, the excess entropy in the pair approximation, and the dispersion relation of longitudinal acoustic-like collective excitations are calculated. These theoretical results are compared with the results from molecular dynamics simulations and good overall agreement is observed in the investigated regime of screening and coupling parameters.