It was recalled that glasses with a good ionic conductivity always contained a high concentration of monovalent ions that acted as charge carriers. Because of this high concentration, ionic transport was governed not only by interactions between the ions and the glass network, but also by interactions between the moving ions themselves. By starting with reasonable assumptions concerning chemical bonding and structure, the local motions and long-range transitions of mobile ions were distinguished. Ionic motion was considered in terms of the general aspects of transport processes in solids, such as interactions of moving ions with the surrounding network or with other mobile ions, and the effect of the structure upon the geometry of transport pathways. Various types of correlated motion, and their importance in ionic transport and related phenomena (tracer diffusion, conductivity, frequency response) and their dependence upon the glass composition and temperature were considered.

H.Kahnt: Journal of Non-Crystalline Solids, 1996, 203, 225-31