A DENSITY-FUNCTIONAL THEORY FORMULATION OF THE REACTION FIELD MODEL OF SOLVENT EFFECTS

It is possible to reformulate the reaction field (RF) model of continu um solvent effects, by considering an approximate expression describin g the energy changes from one ground state to another, in the frame of density functional theory (DFT). The energy functional for an arbitra ry electronic system coupled to a spin-independent electrostatic exter nal perturbation is used to derive the well-known Born expression givi ng the electrostatic component of the solvation energy of an atomic io n. The approximate RF-DFT model is illustrated for a series of represe ntative singly positive and negatively charged atomic ions. A Kohn-Sha m (Ks)-like formalism is then proposed to compute solvation energies w ithin a self-consistent field scheme. The extension of the RF-DFT mode l to molecular systems is also outlined. (C) 1995 John Wiley & Sons, I nc.