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arXiv · 1608.08430

Free-energy functional of the Debye-Hückel model of simple fluids

R. Piron·T. Blenski
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Abstract

The Debye-Hückel approximation to the free-energy of a simple fluid is written as a functional of the pair correlation function. This functional can be seen as the Debye-Hückel equivalent to the functional derived in the hyper-netted chain framework by Morita and Hiroike, as well as by Lado. It allows one to obtain the Debye-Hückel integral equation through a minimization with respect to the pair correlation function, leads to the correct form of the internal energy, and fulfills the virial theorem.

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R. Piron, T. Blenski. 2016-09-07. Free-energy functional of the Debye-Hückel model of simple fluids. https://doi.org/10.1103/physreve.94.062128

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