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. 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.
C. P. Royall, A. Malins, A. J. Dunleavy & R. Pinney
Chapter 18 of Fragility of Glass-forming Liquids
Edited by: A. L. Greer, K. F. Kelton & S. Sastry
Published by Hindustan Book Agency, New Delhi, India