Mixed mobile ion effect and cooperative motions in silver-sodium phosphate glasses

Abstract

The conduction pathways and the extraordinary weak mixed mobile ion effect (MMIE) in AgxNa1-xPO3 glasses have been investigated by bond-valence analysis of reverse Monte Carlo produced structural models. We find that the MMIE is suppressed in this system due to a common cooperative hopping process, where both Ag and Na participate. This finding is in strong contrast to glass systems exhibiting a pronounced MMIE, where the two types of mobile ions have distinctly different conduction pathways and the M ions tend to block the pathways for the N ions and vice versa. © 2008 The American Physical Society.