Electronic Structure of Transition Metals Fe, Ni and Cu in the GW Approximation

TL;DR

This paper uses the GW approximation to calculate the electronic band structures of transition metals Fe, Ni, and Cu, showing improved agreement with experiments for band widths but highlighting limitations in exchange splitting and spectral features.

Contribution

It provides detailed analysis of static and dynamical screening effects in GW calculations for transition metals, emphasizing the importance of dynamical correlations.

Findings

Occupied 3d band width matches experiments better than LSDA

GW does not reproduce exchange splitting and satellite features

Dynamical screening narrows band widths significantly

Abstract

The quasiparticle band structures of 3d transition metals, ferromagnetic Fe, Ni and paramagnetic Cu, are calculated by the GW approximation. The width of occupied 3d valence band, which is overestimated in the LSDA, is in good agreement with experimental observation. However the exchange splitting and satellite in spectra are not reproduced and it is required to go beyond the GW approximation. The effects of static screening and dynamical correlation are discussed in detail in comparison with the results of the static COHSEX approximation. The dynamical screening effects are important for band width narrowing.