Mutual diffusion and self-diffusion in the frictional formalism of non-equilibrium thermodynamics
Abstract
Conceptual differences between mutual diffusion and self-diffusion are analysed using the frictional formalism of non-equilibrium thermodynamics. Expressions for the two diffusion coefficients are derived and it is shown that the friction coefficient operative in self-diffusion is different from the corresponding friction coefficient in mutual diffusion. A common error in the recent literature concerning the expression for the mutual-diffusion coefficient is corrected.