First-order layering and critical wetting transitions in non-additive hard sphere mixtures

Paul Hopkins; Matthias Schmidt

doi:10.1103/physreve.83.050602

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arXiv · 1105.1618

First-order layering and critical wetting transitions in non-additive hard sphere mixtures

Paul Hopkins·Matthias Schmidt

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Abstract

Using fundamental-measure density functional theory we investigate entropic wetting in an asymmetric binary mixture of hard spheres with positive non-additivity. We consider a general planar hard wall, where preferential adsorption is induced by a difference in closest approach of the different species and the wall. Close to bulk fluid-fluid coexistence the phase rich in the minority component adsorbs either through a series of first-order layering transitions, where an increasing number of liquid layers adsorbs sequentially, or via a critical wetting transition, where a thick film grows continuously.

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Paul Hopkins, Matthias Schmidt. 2011-05-09. First-order layering and critical wetting transitions in non-additive hard sphere mixtures. https://doi.org/10.1103/physreve.83.050602

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