ELECTROKINETIC PROPERTIES OF A CHARGED TRACER IN A TIME-DEPENDENT EXTERNAL-FIELD

In a previous paper [Cruz de Leon et al., Chem. Phys. Lett. 207, 294 ( 1993)], we have derived a formalism to calculate the dynamic friction function of a charged tracer macroparticle in a multicomponent ionic s olution. Here we apply this theoretical scheme to describe the electro kinetic properties of a charged tracer immersed in a solution in the p resence of a time-dependent external driving force. We derive analytic expressions for the self-diffusion coefficient and the electrophoreti c mobility. We compute the Van Hove self-correlation function and comp are it with previous results. As an example we compute the electrophor etic mobility in the presence of a time-independent external driving f orce within well-defined limits and approximations. We obtain complete results in the absence of hydrodynamic interactions. Our results deri ved here provide a framework to describe the dynamics of a charged tra cer.