ELECTROSTATIC DOUBLE-LAYER INTERACTION BETWEEN 2 CHARGED ION-PENETRABLE SPHERES - AN EXACTLY SOLVABLE MODEL

The exact expression for the interaction energy between two charged ion-penetrable spheres is obtained on the basis of the linearized Poisson-Boltzmann equation without recourse to Derjaguin’s approximation. This enables us to check the validity of Derjaguin’s method as well as that of its extension to the interaction of unequal spheres by Hogg, Healy, and Fuerstenau (Trans. Faraday Soc.62, 1638 (1966)). It is shown that Derjaguin’s method is quite a good approximation for the case of two interacting charged ion-penetrable spheres. © 1993 Academic Press, Inc.