Beta-relaxation of non-polymeric liquids close to the glass transition

TL;DR

This study investigates dielectric beta-relaxation in a non-polymeric liquid near the glass transition, revealing temperature-independent peak frequency in equilibrium and a new parameter with Arrhenius behavior unaffected by the transition.

Contribution

It introduces a novel annealing-state independent parameter linking loss and peak frequency with simple Arrhenius temperature dependence.

Findings

Beta loss peak frequency is temperature-independent in equilibrium.

Maximum dielectric loss varies strongly with temperature.

A new parameter remains constant across different annealing states.

Abstract

Dielectric beta-relaxation in a pyridine-toluene solution is studied close to the glass transition. In the equilibrium liquid state the beta loss peak frequency is not Arrhenius (as in the glass) but virtually temperature-independent, while the maximum loss is strongly temperature-dependent. Both loss peak frequency and maximum loss exhibit thermal hysteresis. A new annealing-state independent parameter involving loss and loss peak frequency is identified. This parameter has a simple Arrhenius temperature-dependence and is unaffected by the glass transition.