The serial sectioning technique was used to study the diffusion of 35SO42- ions in single crystals, in the intrinsic range. The results (table 71) could be described by:

D (cm2/s) = 0.187 exp[-1.23(eV)/kT]

Diffusion and Solubility of SO42- in NaCl and KCl Single Crystals. M.Bénière, F.Bénière, M.Chemla: Solid State Communications, 1973, 13[9], 1339-43