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arXiv · 2208.12973

Magnetic bond-order potential for iron-cobalt alloys

Aleksei Egorov·Aparna P. A. Subramanyam·Ziyi Yuan·Ralf Drautz·Thomas Hammerschmidt
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Abstract

For large-scale atomistic simulations of magnetic materials, the interplay of atomic and magnetic degrees of freedom needs to be described with high computational efficiency. Here we present an analytic bond-order potential (BOP) for iron-cobalt, an interatomic potential based on a coarse-grained description of the electronic structure. We fitted BOP parameters to magnetic and non-magnetic density-functional theory (DFT) calculations of Fe, Co, and Fe-Co bulk phases. Our BOP captures the electronic structure of magnetic and non-magnetic Fe-Co phases. It provides accurate predictions of structural stability, elastic constants, phonons, point and planar defects, and structural transformations. It also reproduces the DFT-predicted sequence of stable ordered phases peculiar to Fe-Co and the stabilization of B2 against disordered phases by magnetism. Our Fe-Co BOP is suitable for atomistic simulations with thousands and millions of atoms.

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Aleksei Egorov, Aparna P. A. Subramanyam, Ziyi Yuan, Ralf Drautz, Thomas Hammerschmidt. 2022-08-27. Magnetic bond-order potential for iron-cobalt alloys. https://doi.org/10.1103/physrevmaterials.7.044403

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