Estimating the density-scaling exponent of a monatomic liquid from its pair potential

Lasse Bøhling; Nicholas P. Bailey; Thomas B. Schrøder; Jeppe C. Dyre

doi:10.1063/1.4869114

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arXiv · 1401.2606

Estimating the density-scaling exponent of a monatomic liquid from its pair potential

Lasse Bøhling·Nicholas P. Bailey·Thomas B. Schrøder·Jeppe C. Dyre

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Abstract

This paper investigates two conjectures for calculating the density dependence of the density-scaling exponent of a single-component, pair-potential liquid with strong virial potential-energy correlations. The first conjecture gives an analytical expression for the density-scaling exponent directly in terms of the pair potential. The second conjecture is a refined version of this, which involves the most likely nearest-neighbor distance determined from the pair-correlation function. The two conjectures for the density-scaling exponent are tested by simulations of three systems, one of which is the standard Lennard-Jones liquid. While both expressions give qualitatively correct results, the second expression is more accurate.

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Lasse Bøhling, Nicholas P. Bailey, Thomas B. Schrøder, Jeppe C. Dyre. 2014-03-08. Estimating the density-scaling exponent of a monatomic liquid from its pair potential. https://doi.org/10.1063/1.4869114

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