Propylene Carbonate Reexamined: Mode-Coupling $\beta$ Scaling without Factorisation ?

TL;DR

This study reexamines the dynamic susceptibility of propylene carbonate above the critical temperature using various scattering techniques, revealing a variable beta scaling regime and consistent mode-coupling parameters despite some deviations from universal asymptotics.

Contribution

It provides a comprehensive analysis of propylene carbonate's dynamic susceptibility, demonstrating beta scaling behavior and mode-coupling parameters across different observables.

Findings

Beta scaling regime varies with alpha relaxation strength.

Mode-coupling fits give λ=0.72 and T_c=182 K.

Not all observables reach universal asymptotics.

Abstract

The dynamic susceptibility of propylene carbonate in the moderately viscous regime above $T_{\rm c}$ is reinvestigated by incoherent neutron and depolarised light scattering, and compared to dielectric loss and solvation response. Depending on the strength of $\alpha$ relaxation, a more or less extended $\beta$ scaling regime is found. Mode-coupling fits yield consistently $\lambda=0.72$ and $T_{\rm c}=182 $K, although different positions of the susceptibility minimum indicate that not all observables have reached the universal asymptotics.