Silver ion dynamics in mixed network former glasses: evidence of correlation with characteristic lengths and network structure

Abstract

We have presented conductivity spectra at different temperatures for mixed network former silver borophosphate glasses. By mapping the conductivity spectra onto time dependence of the mean square displacement of mobile ions in the framework of linear response theory, we have obtained two characteristic lengths of ion dynamics viz characteristic mean square displacement at which crossover from diffusive to subdiffusive ion dynamics and spatial extent of localized motion of mobile silver ions occur. We have shown that the mixed network effect in these glasses is correlated to these characteristic lengths which are strongly influenced by the Coulomb repulsion between the mobile silver ions as well as the interaction between the mobile ions and the glass network.