Scientist working in the Center for Computational Science & e-Systems, Japan Atomic Energy Agency.

Spotted an error on this site?
Corrections appreciated, please email alex (at) alexmalins.com or leave a comment.

Investigating isomorphs with the topological cluster classification

The behaviour of 11A clusters along Kob-Andersen Isomorphs (a) statics & (b) cluster lifetimes.

The behaviour of 11A clusters along Kob-Andersen Isomorphs (a) statics & (b) cluster lifetimes.


Isomorphs are lines in the density-temperature plane of certain “strongly correlating” or “Roskilde simple” liquids where two-point structure and dynamics have been shown to be close to identical up to a scale transformation. Here we consider such a liquid, a Lennard-Jones glass former, and investigate the behavior along isomorphs of higher-order structural and dynamical correlations. We then consider an inverse power law reference system mapped to the Lennard-Jones system [Pedersen et al., Phys. Rev. Lett. 105, 157801 (2010)]. Using the topological cluster classification to identify higher-order structures, in both systems we find bicapped square antiprisms, which are known to be a locally favored structure in the Lennard-Jones glass former. The population of these locally favored structures is up to 80% higher in the Lennard-Jones system than the equivalent inverse power law system. The structural relaxation time of the two systems, on the other hand, is almost identical, and the four-point dynamical susceptibility is marginally higher in the inverse power law system. Upon cooling, the lifetime of the locally favored structures in the Lennard-Jones system is up to 40% higher relative to the reference system.

Alex Malins, Jens Eggers & C. Patrick Royall
The Journal of Chemical Physics 139 (23), 234505 (2013)


Page last updated: 22nd August 2020

PDF: download
DOI: http://dx.doi.org/10.1063/1.4832897
ArXiv: http://arxiv.org/abs/1307.551

Leave a reply

Your email address will not be published.