WEIGHTED-DENSITY-FUNCTIONAL THEORY OF ELECTRODE-ELECTROLYTE INTERFACE - BEYOND THE PRIMITIVE MODEL

A weighted-density-functional theory is developed for an inhomogeneous electrolyte solution near a planar charged electrode using a nonprimitive three-component model consisting of one neutral and two charged hard-sphere components representing the solvent and the ions, respectively. Both the hardsphere and electrical contributions to the one-particle correlation function are obtained nonperturbatively by evaluating the direct-correlation functions of the corresponding uniform system using appropriate effective densities. Numerical results on the density profiles of the ions and the solvent molecules and also the mean electrostatic potential near the electrode surface at several surface-charge densities are presented to obtain insight into the layering and charge-inversion phenomena occurring at the interface.