Microscopic origin of anelastic relaxtions in polyethylene oxide-sodium thiocyanate complexes

The temperature behavior (100-400 K) of the mechanical characteristics (internal friction and resonant frequency) of polyethyleneoxide-NaSCN polymeric electrolytes reveals the presence of anelastic relaxations, which arise from local and cooperative microscopic motions. The low-temperature ? relaxation is explained in terms of a relaxation time distribution, which is interpreted as arising from random deviations in the local arrangement of the relaxing particles. Moreover, the elastic and anelastic features, as a function of the salt content, give some insight concerning their microscopic origin and the connection between the structure and the fast ion dynamics in this kind of systems.