Relaxation in Ge 2Se 98 and As 2Se 98 glasses

Abstract

Mercury dilatometry and differential scanning calorimetry were used to study structural relaxation of Ge 2Se 98 and As 2Se 98 glasses. Tool-Narayanaswamy–Moynihan model was used to fit the experimental data. Single set of volume and enthalpy relaxation parameters describing all performed measurements was determined for each studied glass. Volumetric and enthalpic TNM parameters were for both glasses compared with each other as well as with values for amorphous selenium determined earlier. The comparison of the apparent activation energy of structural relaxation with the activation energy of viscous flow was made for accessible low-Ge/As-content data in Ge x Se 1− x and As x Se 1− x systems. Moreover, several non-fitting methods of TNM parameters estimation were applied to our data. A good agreement with curve-fitting results was achieved for most methods which is consistent with our previous results on amorphous selenium and polyvinyl acetate.