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arXiv · 1712.07427

Rich Ground State Chemical Ordering in Nanoparticles: Exact Solution of a Model for Ag-Au Clusters

Peter Mahler Larsen·Karsten Wedel Jacobsen·Jakob Schiøtz
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Abstract

We show that nanoparticles can have very rich ground state chemical order. This is illustrated by determining the chemical ordering of Ag-Au 309-atom Mackay icosahedral nanoparticles. The energy of the nanoparticles is described using a cluster expansion model, and a Mixed Integer Programming (MIP) approach is used to find the exact ground state configurations for all stoichiometries. The chemical ordering varies widely between the different stoichiometries, and display a rich zoo of structures with non-trivial ordering.

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Peter Mahler Larsen, Karsten Wedel Jacobsen, Jakob Schiøtz. 2017-12-20. Rich Ground State Chemical Ordering in Nanoparticles: Exact Solution of a Model for Ag-Au Clusters. https://doi.org/10.1103/physrevlett.120.256101

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