The case of diffusion in solids, with random activation energies for individual jumps, was analyzed. Experimentally observed relationships between the activation energies for diffusion in metallic glasses and in the corresponding crystals was explained by making reasonable assumptions. The activation energy was shown to be not the most probable one, but one which was quite close to the minimum that was permitted (by the percolation mechanism) for the activation energy of individual jumps. The activation energy for an interstitial solute depended parametrically upon the mean solute concentration.

L.N.Davydov, Z.A.Spolnik: Physica Status Solidi B, 1995, 191[1], 57-66