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arXiv · 0803.2199

Density scaling as a property of strongly correlating viscous liquids

Thomas B. Schrøder·Ulf R. Pedersen·Jeppe C. Dyre
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Abstract

We address a recent conjecture according to which the relaxation time $\tau$ of a viscous liquid obeys density scaling ($\tau=F(\rho^\gamma/T)$ where $\rho$ is density) if the liquid is ``strongly correlating,'' i.e., has almost 100% correlation between equilibrium virial and potential-energy fluctuations [Pedersen {\it et al.}, PRL {\bf 100}, 011201 (2008)]. Computer simulations of two model liquids - an asymmetric dumbbell model and the Lewis-Wahnstr\"om OTP model - confirm the conjecture and demonstrate that the scaling exponent $\gamma$ can be accurately predicted from equilibrium fluctuations.

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Thomas B. Schrøder, Ulf R. Pedersen, Jeppe C. Dyre. 2008-03-14. Density scaling as a property of strongly correlating viscous liquids. https://doi.org/10.1103/physreve.80.041502

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