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arXiv · 1311.4471

Glassy clusters: Relations between their dynamics and characteristic features of their energy landscape

Abstract

Based on a recently introduced metric for measuring distances between configurations, we in- troduce distance-energy (DE) plots to characterize the potential energy surface (PES) of clusters. Producing such plots is computationally feasible on the density functional (DFT) level since it re- quires only a set of a few hundred stable low energy configurations including the global minimum. By comparison with standard criteria based on disconnectivity graphs and on the dynamics of Lennard- Jones clusters we show that the DE plots convey the necessary information about the character of the potential energy surface and allow to distinguish between glassy and non-glassy systems. We then apply this analysis to real systems on the DFT level and show that both glassy and non-glassy clusters can be found in simulations. It however turns out that among our investigated clusters only those can be synthesized experimentally which exhibit a non-glassy landscape.

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Sandip De, Bastian Schaefer, Ali Sadeghi, Michael Sicher, D. G. Kanhere, Stefan Goedecker. 2013-11-18. Glassy clusters: Relations between their dynamics and characteristic features of their energy landscape. https://arxiv.org/abs/1311.4471

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