Transport properties of Lennard-Jones fluids: Freezing density scaling along isotherms

S. A. Khrapak; A. G. Khrapak

doi:10.1103/physreve.103.042122

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arXiv · 2109.14066

Transport properties of Lennard-Jones fluids: Freezing density scaling along isotherms

S. A. Khrapak·A. G. Khrapak

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Abstract

It is demonstrated that properly reduced transport coefficients (self-diffusion, shear viscosity, and thermal conductivity) of Lennard-Jones fluids along isotherms exhibit quasi-universal scaling on the density divided by its value at the freezing point. Moreover, this scaling is closely related to the density scaling of transport coefficients of hard-sphere fluids. The Stokes-Einstein relation without the hydrodynamic diameter is valid in the dense fluid regime. The lower density boundary of its validity can serve as a practical demarcation line between gas-like and liquid-like regimes.

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S. A. Khrapak, A. G. Khrapak. 2021-09-28. Transport properties of Lennard-Jones fluids: Freezing density scaling along isotherms. https://doi.org/10.1103/physreve.103.042122

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