The electrical conductivity and conductivity relaxation of xK2O-(100-x)TeO2 glasses were investigated at 40Hz to 200kHz and 300 to 473K. From the density and molar volume, it may be noticed that with increasing K2O content the density decreased while the molar volume increased highlighting the fact that more non-bridging O atoms were formed in the network as the concentration of K2O was increased. The Anderson-Stuart model was employed to explain the dc activation energy. The frequency-dependent electrical data were analyzed in the framework of the conductivity and modulus formalisms. The decrease of the conductivity relaxation time with increasing content of K2O was explained in the framework of the structural model of tellurite glasses. The variation of the stretched exponential parameter with composition was compared with those of lithium and sodium tellurite glasses and was explained in terms of cation-cation distance correlation.

Ionic Conductivity and Conductivity Relaxation of Potassium Tellurite Glasses. M.M.El-Desoky, H.S.Ragab: Physica Status Solidi A, 2005, 202[6], 1088-95