Free energy functionals and the structure of the uniform hard-sphere fluid

Abstract

Tarazona's weighted density approximation (WDA) to the intrinsic free-energy functional is used to investigate the equilibrium structure of a uniform hard-sphere fluid. The WDA results for the radial distribution function g(r), obtained by fixing one particle at the origin and computing the resulting density profile, are close to those of simulation for all bulk (fluid) densities. Moreover, the cavity function y(r) and the bridge function b(r) are in good agreement with simulation for separations r inside the hard-core. Our results provide further evidence that the WDA provides an accurate description of highly inhomogeneous hard-sphere fluids.