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arXiv · 1112.3804

Caged clusters in Al$_{11}$Ir$_4$: structural transition and insulating phase

Marek Mihalkovič·C. L. Henley
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Abstract

Using pair potentials fitted to an ab--initio database, combined with replica--exchange simulated annealing, we show the complex, quasicrystal-related Al$_{11}$Ir$_4$ compound contains a new version of the "pseudo-Mackay" icosahedral cluster, with non-icosahedral inner Al$_{10}$Ir and/or Al$_9$Ir clusters that exist in various orientations and account for partial occupancies in the reported structure. Two different compositions show first-order transitions to orientationally ordered phases doubling the (cubic) unit cell, which are respectively metallic and insulating.

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Marek Mihalkovič, C. L. Henley. 2012-06-23. Caged clusters in Al$_{11}$Ir$_4$: structural transition and insulating phase. https://arxiv.org/abs/1112.3804

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