FIRST-PRINCIPLES CALCULATIONS OF THE INSTABILITIES IN Fe-(Ni, Co, Pt) ALLOYS

Abstract

First-principles calculations using the Korringa-Kohn-Rostocker method and the Coherent-Potential Approximation for Fe-Ni, Fe-NiCo and Fe-Pt alloys show that several features are responsible for the Invar anomalies. Atomic short range ordering in the alloys is responsible for the appearance of antiferromagnetic and non-colinear magnetic moments. The antiferromagnetic contributions are responsible for two effects, the negative anharmonicity due to the tendency of the alloys to have a smaller lattice constant, as well as the tendency to have a larger lattice constant because of additional density of states of antibonding majority-spin orbitals at the Fermi level, which simultaneously stabilizes the antiferromagnetic moments.

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Cite this paper

@inproceedings{ENTELaFIRSTPRINCIPLESCO, title={FIRST-PRINCIPLES CALCULATIONS OF THE INSTABILITIES IN Fe-(Ni, Co, Pt) ALLOYS}, author={P. ENTELa and Valer-Alin Crisan and Hiroko Akai} }