Dielectric response of colloidal spheres in non-symmetric electrolytes

Using a method introduced by Albano et al. (Physica A 99 (1979) 293 and Physica A 102 (1980) 105) based on the concept of excess densities in the sense of Gibbs, and excess fluxes, an analytical expression for the frequency-dependent dipolar coefficient of a charged sphere in a electrolyte valid for all double layer thicknesses for low and high zeta potentials is derived. The found expression is compared to the analytical formulae of Fixman, Hinch et al. and O'Brien in their range of validity and to the numerical simulation of Mangelsdorf and White. (C) 2003 Elsevier Science B.V. All rights reserved.