Self-diffusion in liquid sodium at constant volume and constant pressure

Abstract

Abstract The self-diffusion coefficient of liquid sodium has been determined in the temperature range melting point to 300°C, under both constant pressure and constant volume conditions. The experimental technique is described in detail and current theories are reviewed in the light of the results obtained. None of the theoretical approaches is entirely correct in predicting the experimentally observed data. This is probably because there is more than one diffusion process operative in the liquid. It is, however, concluded that models of the fluctuation type most accurately describe observed conditions. The critical fluctuation concept is thought not to be applicable.