Single-exponential activation behavior behind the super-Arrhenius relaxations inglass-forming liquids

Abstract

The reported relaxation time for several typical glass-forming liquids was analyzed by usinga kinetic model for liquids which invoked a new kind of atomic cooperativity—thermodynamiccooperativity. The broadly studied ‘cooperative length’ was recognized as the kineticcooperativity. Both cooperativities were conveniently quantified from the measuredrelaxation data. A single-exponential activation behavior was uncovered behind thesuper-Arrhenius relaxations for the liquids investigated. Hence the mesostructure ofthese liquids and the atomic mechanism of the glass transition became clearer.