On the Glass Transition Temperature in Covalent Glasses
نویسندگان
چکیده
We give a simple demonstration of the formula relating the glass transition temperature, Tg, to the molar concentration x of a modifier in two types of glasses: binary glasses, whose composition can be denoted by XnYm+xMpYq, with X an element of III-rd or IV -th group (e.g. B, or Si, Ge), while MpYq is an alkali oxide or chalcogenide; next, the network glasses of the type Ax B1−x, e.g. Gex Se1−x, Six Te1−x, etc. After comparison, this formula gives an exact expression of the parameter β of the modified Gibbs-Di Marzio equation.
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