Mechanical relaxation of some tellurovanadate glasses

The ultrasonic relaxation process of ZnO-TeO2-V2O5 and CeO2-TeO2-V2O5 glasses was investigated in terms of the central force model of acoustically active two-well systems. The theoretical treatment of the vibrations of two-well systems revealed that, the equilibrium interatomic separation, the number of loss centers and the activation energy are affected with the mutual potential energy of the studied glasses. The number of loss centers is related to the compositional dependence of the elastic moduli and the average ring diameter. The results showed that degree of elongation or contraction of the two-well system depends on the concentration of CeO2 or ZnO. The theoretically determined longitudinal and transverse deformation potentials due to the acoustic loss produced by two-well systems decrease with the increase of ZnO/CeO2 content.