Thermal analysis of Li2O TeO2 glass

The thermal properties of 0.30Li2O 0.70TeO2 glass are studied. Specific heat, Cp, is measured in the 170∞C < T < 270∞C interval. The Einstein temperature, hAa 840 K, is determined from the temperature course of Cp. In the glass transition interval, the heat capacity undergoes an S-shaped transition from the value, Cgl, of the glass to that of undercooled melt, Cp. It is found that Cgl=Cp 0:62. The activation energy, EOTfU, for structural relaxation depends on a fictive temperature, Tf . For the glass under study, it is demonstrated that: EOTfUa655a 300O 520 Tf ˇ 1U kJ/ mol. ” 2000 Elsevier Science B.V. All rights reserved.