Summary of Diffusion Potentials

The diffusion potential is the generalized thermodynamic driving force that produces fluxes of atomic or molecular species. The diffusion potential reflects the change in energy that results from the motion of a species therefore, it includes energy-storage mechanisms and any constraints on motion. 

4 j = fij -)- k, lj Accounting for the anisotropic equivalent to capillary pressure. K-, the weighted mean curvature, is the rate of energy increase with volume addition (e.g., surface diffusion on a faceted surface). Section 14.2.2. 

2 Again, as in the derivation of Eq. 3.82, quadratic terms in the elastic energy, which are of lower order in importance, have been neglected (see Larche and Cahn [21]). 

22For an ideally viscous material, the strain rate e is linearly related to the applied stress cr by the relation e = (l/rj) r, where rj is the viscosity. 

Kirkaldy and D.J. Young. Diffusion in the Condensed State. Institute of Metals, London, 1987. 

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