Stokes−Einstein Relation in Two- and Three-Dimensional Fluids

Abstract

The Stokes−Einstein relation, relating the self-diffusion coefficient D to the shear viscosity η (D = kBT/2πησ), is tested for two- and three-dimensional fluids. The influence of attractive potential and temperature on the validity of the Stokes−Einstein relation by employing square-well potential is analyzed. A breakdown of the Stokes−Einstein relation is observed at low temperatures for three-dimensional fluid by using the Nigra and Evans(11) model and with that obtained from the velocity autocorrelation function(10) and for two-dimensional fluids by using the Garcia−Rojo et al.(12) model for hard discs.