Effective macroion-macroion potentials in asymmetric electrolytes - art. no. 020401

Effective macroion-macroion potentials in solutions of macroions carrying 6 0 elementary charges and either monovalent or divalent counterions have bee n calculated at different concentrations by means of Monte Carlo simulation s with a consequent inversion of radial distribution functions according to Lyubartsev and Laaksonen [Phys. Rev. E 52, 3730 (1995)]. With monovalent c ounterions, the effective potentials are essentially of a Yukawa type, wher eas with divalent ones, an attractive region appears at short separation. A charge renormalization scheme invoking the cell model and the assumption o f a Yukawa-type potential works favorably only in the case of monovalent co unterions.