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Close to the edge of Fundamental Measure Theory: density functional for hard sphere mixtures

Jose A. Cuesta·Yuri Martinez-Raton·Pedro Tarazona
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Abstract

We analyze the structure of the Fundamental Measure Theory for the free energy density functional of hard sphere mixtures. A comparative study of the different versions of the theory, and other density functional approaches, is done in terms of their generic form for the three-points direct correlation function, which shows clearly the main advantages and problems of the different approximations. A recently developed version for the monocomponent case is extended to mixtures of hard spheres with different radii, and a new prescription is presented to obtain the exact dimensional crossover of those mixtures in the one-dimensional (1D) limit. Numerical results for planar wall-fluid interfaces and for the 1D fluid are presented.

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Jose A. Cuesta, Yuri Martinez-Raton, Pedro Tarazona. 2002-05-13. Close to the edge of Fundamental Measure Theory: density functional for hard sphere mixtures. https://doi.org/10.1088/0953-8984%2F14%2F46%2F307

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