Colloid vibration potential in a concentrated suspension of spherical colloidal particles

A relation between the dynamic electrophoretic mobility of spherical colloi dal particles in a concentrated suspension and the colloid vibration potent ial (CVP) generated in the suspension by a sound wave is obtained from the analogy with the corresponding Onsager relation between electrophoretic mob ility and sedimentation potential in concentrated suspensions previously de rived on the basis of Kuwabara's cell model. The obtained expression for CV P is applicable to the case where the particle zeta potential is low, the p article relative permittivity is very small, and the overlapping of the ele ctrical double layers of adjacent particles is negligible. It is found that CVP shows much stronger dependence on the particle volume fraction phi tha n predicted from the phi dependence of the dynamic electrophoretic mobility . It is also suggested that the same relation holds between the electrokine tic sonic amplitude of a concentrated suspension of spherical colloidal par ticles and the dynamic electrophoretic mobility. (C) 1999 Academic Press.