The isotope effect for 6Li and 7Li self-diffusion in single crystals was investigated (table 168) by determining the relative difference between the mobilities of the isotopes using measurements of the isotopic concentration in sections, and the difference between the average isotopic concentrations in the anode part of a sample and the initial isotopic concentration of a crystal.

Relative Difference between the Mobilities of Positive Ionsof Lithium Isotopes 6Li and 7Li in LiF.V.B.Ptashnik, A.N.Naumov: Fizika Tverdogo Tela, 1968, 10[3], 880-4