On the applicability of the HNC approximation to highly charged polyelectrolytes

Abstract

The hypernetted chain approximation is applied to the interaction of two charged colloidal particles immersed in an electrolyte solution and compared to the classical theory of Verwey–Overbeek. The HNC result is asymptotically correct for either small surface potentials or large particle separations. For strongly charged particles, however, it predicts a short ranged attraction which is absent in the classical theory. It is concluded that a similar attraction recently found by Patey [J. Chem. Phys. 72, 5763 (1980)] is an artifact of the HNC approximation.