- Wednesday, June 20, 2007
- Mean-coordination number dependence of the fragility in Ge-Se-In glass forming liquids
- Published at:Physica. B, Condensed matter, 2007, vol. 389, no2, pp. 275-280
Differential scanning calorimetry measurements have been performed on elemental Se as well as on GexSe94ÀxIn6 (x ¼ 4, 8, and 11 at%) and on GeySe88ÀyIn12 (y ¼ 5, 7, and 9 at%) chalcogenide glasses. From the cooling rate dependence of the ﬁctive temperature,the apparent activation energies, Dh*, and the fragility indices, m, as deﬁned in the strong–fragile glass-forming liquid concept, are determined. It is found that, in Ge–Se–In system, there is an evolution from strong (m ¼ 67) to fragile (m ¼ 116) glass-forming liquids. The dependence of ‘m’ on the mean-coordination number, Z, is also obtained. This dependence is rationalized by assuming that, in this glassy alloy system, there is a tendency for the formation of In2Se3 clusters.
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