A capillary technique was used to investigate the diffusion of 22Na in molten samples of better than 99% purity (table 177). The data for 1022 to 1132C could be described by:

D (cm2/s) = 3.08 x 10-3 exp[-8.7(kcal/mol)/RT]

Self-Diffusion of Na+ and K+ in their Molten Fluorides. K.Grjotheim, S.Zuca: Acta Chemica Scandinavica, 1968, 2[2], 531-7