Molecular Theory of Counterion Conductivity and Self-Diffusion in Polyelectrolyte Solutions

A previous theory of counterion self-diffusion in a polyelectrolyte solution is extended to describe the counterion flow in the presence of an applied electric field. A term proportional to the velocity of the polyion is obtained in a natural way, with no assumptions concerning ``bound'' counterions. The previous expression for the counterion self-diffusion coefficient is regained as a special case. The significance of the formal agreement with the ion binding model is discussed at some length.