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arXiv · 1606.00307

Quasi-particle bands and structural phase transition of iron from Gutzwiller Density-Functional Theory

Tobias Schickling·Jörg Bünemann·Florian Gebhard·Lilia Boeri
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Abstract

We use the Gutzwiller Density Functional Theory to calculate ground-state properties and bandstructures of iron in its body-centered-cubic (bcc) and hexagonal-close-packed (hcp) phases. For a Hubbard interaction $U=9\, {\rm eV}$ and Hund's-rule coupling $J=0.54\, {\rm eV}$ we reproduce the lattice parameter, magnetic moment, and bulk modulus of bcc iron. For these parameters, bcc is the ground-state lattice structure at ambient pressure up to a pressure of $p_{\rm c}=41\, {\rm GPa}$ where a transition to the non-magnetic hcp structure is predicted, in qualitative agreement with experiment ($p_{\rm c}^{\rm exp}=10\ldots 15\, {\rm GPa}$). The calculated bandstructure for bcc iron is in good agreement with ARPES measurements. The agreement improves when we perturbatively include the spin-orbit coupling.

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Tobias Schickling, Jörg Bünemann, Florian Gebhard, Lilia Boeri. 2016-06-01. Quasi-particle bands and structural phase transition of iron from Gutzwiller Density-Functional Theory. https://doi.org/10.1103/physrevb.93.205151

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