Correlation between temperature variations of static and dynamic properties in glass-forming liquids

Abstract

Detailed analysis of the static structure factor S(Q) in several glass-forming liquids reveals that the temperature variations of the width of the main diffraction peak Q(T ) correlate with the fragility of these liquids. This observation suggests a direct connection between rather subtle structural changes and sharp slowing down of structural relaxation in glass-forming liquids. We show that this observation can be rationalized using the Adam-Gibbs approach, through a connection between temperature variations of structural correlation length, lc ∼ 2π/Q, and the size of cooperatively rearranging regions.