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

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 $α$ relaxation, a more or less extended $β$ scaling regime is found. Mode-coupling fits yield consistently $λ=0.72$ and $T_{\rm c}=182 $K, although different positions of the susceptibility minimum indicate that not all observables have reached the universal asymptotics.