Depletion potential in hard-sphere fluids

¹ Fachbereich Physik, Bergische Universität Wuppertal - D-42097 Wuppertal, Germany
² H. H. Wills Physics Laboratory, University of Bristol - Bristol BS8 1TL, UK

Received: 9 February 1999
Accepted: 28 May 1999

Abstract

A versatile new approach for calculating the depletion potential in a hard-sphere mixture is presented. This is valid for any number of components and for arbitrary densities. We describe two different routes to the depletion potential for the limit in which the density of one component goes to zero. Both routes can be implemented within density functional theory and simulation. We illustrate the approach by calculating the depletion potential for a big hard sphere in a fluid of small spheres near a planar hard wall. The density functional results are in excellent agreement with simulations.