Brownian motion of colloidal crystals
Abstract
We study the dynamics of colloidal crystals taking account of the retardation of the interactions due to the finite diffusivity of the counterions. It is shown that the retardation gives rise to electric dipole interactions proportional to the velocities of the macroions. As a consequence the damping rate of the overdamped transverse phonons tends to zero at small wavenumber. This agrees with observation in dynamic light scattering.