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Optimal packing of polydisperse hard-sphere fluids

Junfang Zhang·Ronald Blaak·Emmanuel Trizac·Jose A. Cuesta·Daan Frenkel
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Abstract

We consider the effect of intermolecular interactions on the optimal size-distribution of $N$ hard spheres that occupy a fixed total volume. When we minimize the free-energy of this system, within the Percus-Yevick approximation, we find that no solution exists beyond a quite low threshold ($η\thickapprox 0.260$). Monte Carlo simulations reveal that beyond this density, the size-distribution becomes bi-modal. Such distributions cannot be reproduced within the Percus-Yevick approximation. We present a theoretical argument that supports the occurrence of a non-monotonic size-distribution and emphasizing the importance of finite size effects.

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Junfang Zhang, Ronald Blaak, Emmanuel Trizac, Jose A. Cuesta, Daan Frenkel. 1998-11-29. Optimal packing of polydisperse hard-sphere fluids. https://doi.org/10.1063/1.478426

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