Viscosity of Cux(As2Se3)100−x supercooled melts

The viscosity of Cux(As2Se3)100−x melts (x = 1, 5, 10 and 20) has been measured by the penetration method (8 < log(η/Pa s) < 13). The temperature dependence of the viscosity can be expressed by a simple equation of Arrhenius type. The kinetic fragility obtained from these plots exhibits similar compositional dependence as the heat capacity change in the glass transition range. This behavior is consistent with the assumption that increasing Cu content causes topological changes in the structure of As2Se3 supercooled melts.