The Tg versus Z dependence of glasses of the GeInSe system

doi:10.1016/0022-3093(92)90036-J

Journal of Non-Crystalline Solids

Volume 151, Issue 3, 2 December 1992, Pages 245-252

https://doi.org/10.1016/0022-3093(92)90036-J Get rights and content

Abstract

The results of measurements on the variation of the glass transition temperature (T_g) with the average coordination number (Z) are reported and discussed for glasses of the GeInSe system. The study covers families of compositions with 5 and 8 at.% In, as well as compositions along the GeSe₂In₂Se₃ tie line. In the T_g−Z data of these glasses, a change in slope is seen at $Z ≌ 2.40$ . In addition, maxima in T_g are observed at Z values corresponding to the tie line compositions of the system. An account of these features is given by the existing Phillips model and the chemically ordered network model. Some of the features observed can be explained by the formation of specific structural units in these glasses. The explanations corroborate our conclusion that, in addition to the features which have a topological origin, effects due to local chemical ordering are also observed in the glasses of this system.

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