Glasses were studied by using 19F nuclear magnetic resonance methods. The activation energy for F-ion migration in ZrF4-29.5BaF2-7mol%LaF3 was equal to 0.30eV for temperatures of between 90 and 240C, and the activation energy for F-ion migration in ZrF4-33BaF2-5mol%LaF3 was equal to 0.29eV for temperatures of between 90 and 268C

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