Mechanical relaxation in (AgI)1- x(Ag2MoO4)x ionic glasses

The acoustic absorption at ultrasonic frequencies (ν=5 MHz) and temperatures varying from room temperature down to 100 K in a (AgI)75(Ag2MoO4)25 glassy system reveals a very broad relaxation peak as the effect of two close but different relaxation processes. The activation energy values characterising these processes can be compared to those obtained from the d.c. conductivity data. A structural model has been hypothesized to account for the observed relaxation processes.