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Asymptotic decay of pair correlations in a Yukawa fluid

P. Hopkins·A. J. Archer·R. Evans
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Abstract

We analyse the $r \to \infty$ asymptotic decay of the total correlation function, $h(r)$, for a fluid composed of particles interacting via a (point) Yukawa pair potential. Such a potential provides a simple model for dusty plasmas. The asymptotic decay is determined by the poles of the liquid structure factor in the complex plane. We use the hypernetted-chain closure to the Ornstein-Zernike equation to determine the line in the phase diagram, well-removed from the freezing transition line, where crossover occurs in the ultimate decay of $h(r)$, from monotonic to damped oscillatory. We show: i) crossover takes place via the same mechanism (coalescence of imaginary poles) as in the classical one-component plasma and in other models of Coulomb fluids and ii) leading-order pole contributions provide an accurate description of $h(r)$ at intermediate distances $r$ as well as at long range.

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P. Hopkins, A. J. Archer, R. Evans. 2005-12-16. Asymptotic decay of pair correlations in a Yukawa fluid. https://doi.org/10.1103/physreve.71.027401

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