Interfacial free energy of hard-sphere fluids and solids near a hard wall

A hard-sphere system near a planar structureless hard wall is considered in thermodynamic equilibrium. The associated interfacial free energies are ca lculated both for a bulk fluid and a bulk face-centered-cubic crystal along (111), (110), and (100) orientation. Combining Monte Carlo simulations and thermodynamic integration, we obtain the wall-fluid and the wall-solid int erfacial free energy over the whole range of possible bulk densities. The " exact" computer simulation data are compared to theoretical approximations. For moderate bulk densities, the wall-fluid interfacial free energies comp are reasonably well with scaled-particle theory and density functional resu lts. For the wall-crystal interface, we propose a simple analytical cell th eory which yields good agreement with our simulation data over the whole ra nge of bulk crystal densities. [S1063-651X(99)01912-1].