Disentangling density and temperature effects in the viscous slowing down of glassforming liquids

G. Tarjus; D. Kivelson; S. Mossa; C. Alba-Simionesco

doi:10.1063/1.1649732

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arXiv · cond-mat/0309579

Disentangling density and temperature effects in the viscous slowing down of glassforming liquids

G. Tarjus·D. Kivelson·S. Mossa·C. Alba-Simionesco

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Abstract

We present a consistent picture of the respective role of density and temperature in the viscous slowing down of glassforming liquids and polymers. Specifically, based in part upon a new analysis of simulation and experimental data on liquid ortho-terphenyl, we conclude that a zeroth-order description of the approach to the glass transition should be formulated in terms of a temperature-driven super-Arrhenius activated behavior rather than a density-driven congestion or jamming phenomenon. The density plays a role at a quantitative level, but its effect on the viscosity and the structural relaxation time can be simply described via a single parameter, an effective interaction energy that is characteristic of the high temperature liquid regime; as a result, density does not affect the ``fragility'' of the glassforming system.

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G. Tarjus, D. Kivelson, S. Mossa, C. Alba-Simionesco. 2003-09-26. Disentangling density and temperature effects in the viscous slowing down of glassforming liquids. https://doi.org/10.1063/1.1649732

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