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arXiv · 1407.5787

Strong geometric frustration in model glassformers

C. Patrick Royall·Alex Malins·Andrew J. Dunleavy·Rhiannon Pinney
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Abstract

We consider three popular model glassformers, the Kob-Andersen and Wahnström binary Lennard-Jones models and weakly polydisperse hard spheres. Although these systems exhibit a range of fragilities, all feature a rather similar behaviour in their local structure approaching dynamic arrest. In particular we use the dynamic topological cluster classification to extract a locally favoured structure which is particular to each system. These structures form percolating networks, however in all cases there is a strong decoupling between structural and dynamic lengthscales. We suggest that the lack of growth of the structural lengthscale may be related to strong geometric frustration.

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C. Patrick Royall, Alex Malins, Andrew J. Dunleavy, Rhiannon Pinney. 2014-07-22. Strong geometric frustration in model glassformers. https://doi.org/10.1016/j.jnoncrysol.2014.08.017

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