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arXiv · 2410.23694

Supercritical Crossover Lines in the Cell Fluid Model

O. A. Dobush·M. P. Kozlovskii·R. V. Romanik
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Abstract

A cell fluid model with a modified Morse potential is studied. The supercritical states are considered with respect to a possibility to build a separation boundary between liquid-like and gas-like bahaviors. Three different lines are calculated that can be used for this purpose: the locus of the isothermal compressibility maxima, the locus of the thermal expansion coefficient maxima, and the line where the effective chemical potential is zero, M=0. By the symmetry of the functionals for the partition functions, the condition M=0 in fluids is analogous to the absence of an external field in the Ising model.

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O. A. Dobush, M. P. Kozlovskii, R. V. Romanik. 2024-10-31. Supercritical Crossover Lines in the Cell Fluid Model. https://doi.org/10.15407/ujpe70.1.35

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