Dielectric Friction on a Moving Ion. II. Revised Theory

The Born–Fuoss–Boyd–Zwanzig calculation of the dielectric friction coefficient on a moving ion is revised in two ways. The relative motion of the ion and its surrounding fluid is taken into account by standard hydrodynamic methods, with both sticking and slipping boundary conditions. Also, the electrostatic problem of finding the electric field due to a change in a moving medium is formulated and solved exactly. The magnitude of the resulting friction coefficient is smaller than in the B–F–B–Z calculation. When the slipping boundary condition is used, the maximum conductance predicted for a singly charged ion in water is about 46 conductance units.