INTERDIFFUSION IN A ONE-DIMENSIONAL INTERACTING-SYSTEM

The flux of one of the components in a system of two interdiffusing materials was taken to be proportional to the gradient of the chemical potential of that component. The chemical potential was derived from the free energy of mixing in a one-dimensional system. When a negative interaction energy was assumed, the interdiffusion coefficient exhibited a maximum. The height and the sharpness of the minimum decreased with increasing temperature. Because of reasons discussed in the paper, for either positive or negative interactions the influence of composition and temperature on the electrical conductivity is expected to be qualitatively similar to the influence exerted by positive interactions on the interdiffusion coefficient.