It was noted that radioactive 204Tl+ diffused up to 3 times more rapidly than did stable Tl+. This difference was attributed to the effect of the 204Pb2+ daughter element which was produced by β-emissions. A theoretical model accounted satisfactorily for the discrepancy, and indicated that internal sources of cation vacancies were effective in maintaining electroneutrality.

G.C.T.Wei, B.J.Wuensch: Science, 1977, 197[4299], 159-61