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

The acoustic absorption at ultrasonic frequencies (v = 5 MHz) and temperatu res 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 cl ose but different relaxation processes. The activation energy values charac terising these processes can be compared to those obtained from the d.c. co nductivity data. A structural model has been hypothesized to account for th e observed relaxation processes. (C) 1998 Published by Elsevier Science B.V . All rights reserved.