Preparation and properties of Ge4Se96 glass

The chalcogenide glass Ge4Se96 was prepared by melt-quenched method. The characteristic temperatures (the strain point, annealing point, glass transition point, yielding point and soften point) were determined by thermal analysis. The result shows that the glass transition point is 52 °C; the average thermal expansion coefficient is ΔL/L0 = (0.0557∗T−1.7576)/1000. The specific heat of Ge4Se96 glass was measured by stepwise method. The difference in specific heat between amorphous structure and undercooled liquid was determined as ΔCp = 0.1812-5.20 × 10−4T−4.92 × 10−7T2 JK−1 g−1. Based on the result of ΔCp, the Gibbs energy and the entropy curves were calculated, and the Kauzmann temperature was determined as Tk = 233.5 K, which is between that for pure Se glass (216 K) and that for Ge7.4Se92.6 glass (250 K). It indicates that for Ge-Se glass with low Ge content, the Kauzmann temperature increases with increasing the content of Ge.