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arXiv · 0706.3695

Magnetism and local distortions near carbon impurity in $γ$-iron

D. W. Boukhvalov·Yu. N. Gornostyrev·M. I. Katsnelson·A. I. Lichtenstein
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Abstract

Local perturbations of crystal and magnetic structure of $γ$-iron near carbon interstitial impurity is investigated by {\it ab initio} electronic structure calculations. It is shown that the carbon impurity creates locally a region of ferromagnetic ordering with substantial tetragonal distortions. Exchange integrals and solution enthalpy are calculated, the latter being in a very good agreement with experimental data. Effect of the local distortions on the carbon-carbon interactions in $γ$-iron is discussed.

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D. W. Boukhvalov, Yu. N. Gornostyrev, M. I. Katsnelson, A. I. Lichtenstein. 2007-11-01. Magnetism and local distortions near carbon impurity in $γ$-iron. https://doi.org/10.1103/physrevlett.99.247205

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