Dielectric relaxation measurements of the ion dynamics in glassy, molten and crystalline ionic conductors showed general properties independent of chemical composition and

structure. These included the appearance of a near-constant loss at high frequencies/low temperatures and the transition to a many-particle ion-hopping regime at lower frequencies. A combination of molecular dynamics simulation, experimental data analysis and the coupling model was used to characterize the ion dynamics in the near-constant-loss regime, the transition zone, and the many-particle ion-hopping regime. An improved understanding was gained of the origin of the near-constant loss and the evolution of the ion dynamics, from short times when the ions were caged, to long times when they were no longer caged but participate in the many-particle dynamics, giving rise finally to direct-current conductivity. Reasons were given to refute criticism of use of the electric modulus to represent and interpret experimental data.

A Combined Molecular Dynamics Simulation, Experimental and Coupling Model Study of the Ion Dynamics in Glassy Ionic Conductors. K.L.Ngai, J.Habasaki, Y.Hiwatari, C.León: Journal of Physics - Condensed Matter, 2003, 15[16], S1607-32