Glasses were studied by using 19F nuclear magnetic resonance methods. The activation energy for F-ion migration in ZrF4-16BaF2-5LaF3-3AlF3–20LiF-5mol%PbF2 was equal to 0.71eV for temperatures of between 127 and 277C. The spectra for 7Li consisted of 2 superposed lineshapes and it was concluded that a distribution of activation energies was involved.

P.J.Bray, D.E.Hintenlang, R.V.Mulkern, S.G.Greenbaum, D.C.Tran, M.Drexhage: Journal of Non-Crystalline Solids, 1983, 56[1-3], 27-32