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arXiv · 1611.01748

Connection between fragility, mean-squared displacement and shear modulus in two van der Waals bonded glass-forming liquids

Henriette Wase Hansen·Bernhard Frick·Tina Hecksher·Jeppe C. Dyre·Kristine Niss
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Abstract

The temperature dependence of the high-frequency shear modulus measured in the kHz range is compared to the mean-squared displacement measured in the nanosecond range for the two van der Waals bonded glass-forming liquids cumene and 5PPE. This provides an experimental test for the assumption connecting two versions of the shoving model for the non-Arrhenius temperature dependence of the relaxation time in glass formers. The two versions of the model are also tested directly and both are shown to work well for these liquids.

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Henriette Wase Hansen, Bernhard Frick, Tina Hecksher, Jeppe C. Dyre, Kristine Niss. 2017-02-08. Connection between fragility, mean-squared displacement and shear modulus in two van der Waals bonded glass-forming liquids. https://doi.org/10.1103/physrevb.95.104202

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