The Onsager Reciprocity Relations Revisited

Abstract

The Onsager relations are discussed and it is suggested that they should be interpreted as there is a frame of reference where all the transport processes are independent. The concepts are illustrated with isobarothermal diffusion in simple metallic phases as well as complex ionic systems. A transformation from lattice-fixed frame of reference to number-fixed frame gives the Kirkendall effect as a cross effect.