Comment on "classical density functional theory of freezing in simple fluids: numerically induced false solutions"

Abstract

In a recent numerical study [Phys. Rev. E 64, 062501 (2001)] of a discretized free-energy functional for the freezing of a hard-sphere fluid, Valera, Pinski, and Johnson (VPJ) found unphysical, spurious free-energy minima. They concluded that free-energy minima obtained in similar previous work on hard spheres using relatively coarse discretization scales were also numerical artifacts. We show here that this conclusion is erroneous: the qualitatively unphysical results found by VPJ do not originate from the coarseness of the mesh but, rather, are themselves artifacts arising from the particular way in which VPJ discretize the direct correlation function. When a more appropriate discretization scheme is used, as in our own earlier work, the results are physical.