Magnetoelastic coupling in gamma-iron investigated within an ab initio spin spiral approach

Article

关键词: AUGMENTED-WAVE METHOD;    EXCHANGE INTERACTIONS;    ULTRASOFT PSEUDOPOTENTIALS;    FINITE-TEMPERATURE;    ALLOYS;    FE;    CO;    NI;    MAGNETISM;    DYNAMICS;   

DOI  :  10.1103/PhysRevB.84.214422

来源: SCIE

【 摘 要 】

Exchange interactions in alpha- and gamma-Fe are investigated within an ab initio spin spiral approach. We have performed total-energy calculations for different magnetic structures as a function of lattice distortions, related to various cell volumes and the Bain tetragonal deformations. The effective exchange parameters in gamma-Fe are very sensitive to the lattice distortions, leading to the ferromagnetic ground state for the tetragonal deformation or increase of the volume cell. At the same time, themagnetic-structure-independent part of the total energy changes very slowly with the tetragonal deformations. The computational results demonstrate a strong mutual dependence of crystal and magnetic structures in Fe and explain the observable anti-Invar behavior of thermal-expansion coefficient in gamma-Fe.

【 授权许可】

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