INTERACTION POTENTIAL OF A DISPERSION OF COLLOIDAL PARTICLES WITH A NONHOMOGENEOUS SURFACE-POTENTIAL

A theoretical model has been developed that describes the diffuse double layer near a flat plate having an inhomogeneous surface potential. It is shown that the charge is screened not only by the traditional Debye-Huckel screening perpendicular to the wall, but also in the lateral direction of the double layer. This contribution is dependent on the periodicity of the surface potential. The interaction potential has been computed between two plates for a general surface-potential distribution under the assumption that the surface-potential distribution on each plate is constant when they approach. The results show that the interaction potential depends to a large extent on the periodicity of the surface potential.