Correlated electronic structure and chemical bonding of Ce pnictides and gamma-Ce

TL;DR

This study uses advanced computational methods to analyze the electronic structure and bonding in cerium pnictides and gamma-Ce, finding good agreement with experimental lattice data and insights into the role of 4f electrons.

Contribution

It applies LDA/GGA+DMFT with different solvers to systematically investigate spectral properties and bonding in Ce pnictides, comparing approaches for the first time.

Findings

Spectral properties agree with photoelectron spectra at high energies.

Calculated lattice constants match experimental data.

Hubbard I approximation captures bonding despite missing low-energy peaks.

Abstract

We present calculated spectral properties and lattice parameters for cerium pnictides (CeN, CeP, CeAs, CeSb, CeBi) and gamma-Ce, within the LDA/GGA+DMFT (local density approximation/generalized gradient approximation + dynamical mean field theory) approach. The effective impurity model arising in the DMFT is solved by using the spin-polarized T-matrix fluctuation-exchange (SPTF) solver for CeN compound, and the Hubbard I (HI) solver for CeP, CeAs, CeSb, and CeBi. For all the addressed compounds the calculated spectral properties are in reasonable agreement with measured photoelectron spectra at high binding energies. At low binding energies the HI approximation does not manage to capture the Kondo-like peak observed for several of the Ce-pnictides. Nevertheless, the calculated lattice constants are in a good agreement with available experimental data, showing that the such a peak does not play a major role on the bonding properties. Furthermore, the HI calculations are compared to a simpler treatment of the Ce 4f electron as core-like in LDA/GGA for CeP, CeAs, CeSb, and CeBi, and the two approaches are found to give similar results.