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

J. Wuttke·M. Ohl·M. Goldammer·S. Roth·U. Schneider·P. Lunkenheimer·R. Kahn·B. Rufflé·R. Lechner·M. A. Berg
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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.

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J. Wuttke, M. Ohl, M. Goldammer, S. Roth, U. Schneider, P. Lunkenheimer, R. Kahn, B. Rufflé, R. Lechner, M. A. Berg. 1999-08-31. Propylene Carbonate Reexamined: Mode-Coupling $β$ Scaling without Factorisation ?. https://doi.org/10.1103/physreve.61.2730

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