In this article, we present a universal relationship between the glass
transition temperature Tg and the local glass structure. The derivation of
the simplest expression of this relationship and some comparisons with
experimental Tg values have already been reported in a recent letter. We
give here the analytical expression of the parameter β of the Gibbs-Di
Marzio equation and also new experimental probes for the validity of the
relationship, especially in low modified binary glasses.Comment: 31 pages, LaTeX, 16 Postscript figures, [email protected]