Wave functions, electronic localization, and bonding properties for correlated materials beyond the Kohn-Sham formalism

Abstract

Many-body theories such as dynamical mean field theory (DMFT) have enabled the description of the electron-electron correlation effects that are missing in current density functional theory (DFT) calculations. However, there has been relatively little focus on the wave functions from these theories. We present the methodology of the newly developed ELK-TRIQS interface and how to calculate the DFT with DMFT (DFT + DMFT) wave functions, which can be used to calculate DFT + DMFT wave-function-dependent quantities. We illustrate this by calculating the electron localization function (ELF) in monolayer SrVO 3 and CaFe 2 As 2 , which provides a means of visualizing their chemical bonds. Monolayer SrVO 3 ELFs are sensitive to the charge redistribution between the DFT, one-shot DFT + DMFT, and fully charge self-consistent DFT + DMFT calculations. In both tetragonal and collapsed tetragonal CaFe 2 As 2 phases, the ELF changes weakly with correlation-induced charge redistribution of the hybridized As p and Fe d states. Nonetheless, the interlayer As-As bond in the collapsed tetragonal structure is robust to the changes at and around the Fermi level.

Impact of electron correlations on the $\mathbf{k}$-resolved electronic structure of PdCrO$_{2}$ revealed by Compton scattering

“…This so-called ELK+TRIQS DFT+DMFT framework is described in Ref. [28]. Further discussion of interfacing the APW+lo DFT basis with the DMFT Anderson's impurity model is found in Ref.…”

“…The DFT outputs were interfaced to the TRIQS/DFTTools application of the TRIQS library [31] by constructing Wannier projectors, as described in Ref. [28], for all the Cr 3d-states within a correlated energy window of [−8.5, 3] eV relative to the Fermi level.…”

Impact of electron correlations on the k-resolved electronic structure of PdCrO2 revealed by Compton scattering

“…We have used the full potential augmented plane-wave plus local orbitals (APW+lo) ELK code [26] in combination with the toolbox for research on interacting quantum systems (TRIQS) library [27]. This so-called ELK+TRIQS DFT+DMFT framework is described in [28]. Further discussion of interfacing the APW+lo DFT basis with the DMFT Anderson's impurity model is found in [29].…”

Tailoring Optical Properties in Transparent Highly Conducting Perovskites by Cationic Substitution

“…Note that the value of U used in the current work was larger than the commonly adopted DMFT calculations in which the locality of correlations was handled within Wannier space. [ 60 ] Instead, the DFT + DMFT method used in this work was derived from the stationary Luttinger–Ward functional, [ 57 ] the implementation of which postulates the locality of the correlation in real space. [ 56 ] For SrMoO 3 , the five d orbitals of Mo were treated as correlated orbitals and the U and J corresponding to Mo 4d orbitals were set to 4.50 and 0.45 eV, respectively.…”