Conductivity spectra were determined for ion-conducting glasses of the forms, B2O3-(0.56Li2O,0.45LiBr) and Ag2S•GeS2, at frequencies which ranged over more than 13 decades. It was found that the conductivities of both glasses revealed the existence of 2 power-law exponents. One of these was the Jonscher exponent, while the other was greater than unity. The results were explained in terms of a so-called unified site-relaxation model.

C.Cramer, K.Funke, B.Roling, T.Saatkamp, D.Wilmer, M.D.Ingram, A.Pradel, M.Ribes, G.Taillades: Solid State Ionics, 1996, 86-88[1], 481-6