Connection between the glass transition temperature T-g and the Arrhenius temperature T-A in supercooled liquids

摘要

At high temperatures the structural relaxation time in liquids has Arrhenius temperature dependence. At lowering temperature, temperature dependence changes to a super Arrhenius at some temperature T-A. This temperature is an important point for the structural relaxation dynamics in supercooled liquids because it reflects the transition to collective relaxation. Here we derive a relation between T-A, the glass transition temperature T-g and fragility. We show that the ratio T-g/T-A increases with increasing fragility of a liquid. The derived relation is in agreement with the experimental data in a series of molecular, hydrogen bonding and two inorganic glass-formers. (C) 2016 Elsevier B.V. All rights reserved.