paper

Electronic Structure of KFe $_{2}$ Se $_{2}$ from First Principles Calculations

arXiv:1012.5621 · doi:10.1088/0256-307X/28/5/057402

Abstract

Electronic structure and magnetic properties for iron-selenide KFe $_{2}$ Se $_{2}$ are studied by first-principles calculations. The ground state is stripe-like antiferromagnetic with calculated 2.26 $I^¼_{B}$ magnetic moment on Fe atoms; and the $J_{1}$ , $J_{2}$ coupling strengths are calculated to be 0.038 eV and 0.029 eV. The states around $E_{F}$ are dominated by the Fe-3d orbitals which hybridize noticeably to the Se-4p orbitals. While the band structure of KFe $_{2}$ Se $_{2}$ is similar to a heavily electron-doped BaFe $_{2}$ As $_{2}$ or FeSe system, the Fermi surface of KFe $_{2}$ Se $_{2}$ is much closer to \fs11 system since the electron sheets around $M$ is symmetric with respect to $x$ - $y$ exchange. These features, as well as the absence of Fermi surface nesting, suggest that the parental KFe $_{2}$ Se $_{2}$ could be regarded as an electron over-doped 11 system with possible local moment magnetism.

accepted by Chinese Physics Letter, to appear as Chinese Physics Letter, Vol 28, page 057402 (2011)

Electronic Structure of KFe2​Se2​ from First Principles Calculations

Abstract

Electronic Structure of KFe $_{2}$ Se $_{2}$ from First Principles Calculations