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arXiv · 1704.06725

Inhomogeneous fluid of penetrable-spheres: application of the random phase approximation

Yan Xiang·Derek Frydel
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Abstract

The focus of the present work is the application of the random phase approximation (RPA), derived for inhomogeneous fluids [Frydel and Ma, Phys. Rev. E 93, 062112 (2016)], to penetrable-spheres. As penetrable-spheres transform into hard-spheres with increasing interactions, they provide an interesting case for exploring the RPA, its shortcomings, and limitations, the weak- versus the strong-coupling limit. Two scenarios taken up by the present study are a one-component and a two-component fluid with symmetric interactions. In the latter case, the mean-field contributions cancel out and any contributions from particle interactions are accounted for by correlations. The accuracy of the RPA for this case is the result of a somewhat lucky cancellation of errors.

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Yan Xiang, Derek Frydel. 2017-04-22. Inhomogeneous fluid of penetrable-spheres: application of the random phase approximation. https://doi.org/10.1063/1.4983129

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