LONG-RANGE ELECTROSTATIC ATTRACTION BETWEEN NEUTRAL SURFACES

The interaction between two spherical colloids immersed in an electrolyte of screening constant κ is studied using the recent charge regulation primitive model. The charge of the particles results from the adsorption of positive and/or negative ions onto the colloidal surfaces. The ion-ion correlations induce an effective attraction between colloids which decreases at large distances as exp-2κr/r2 for small colloids (r being the center to center distance) and as exp-2κh/h for large colloids (h being the surface to surface distance). © 1995 The American Physical Society.