Effect of Coulomb correlations on the electronic structure of bulk V2Se2O: a DFT+DMFT study

Abstract

We present results of density functional theory (DFT) plus dynamical mean-field theory (DFT+DMFT) calculations of the electronic structure of bulk paramagnetic V₂Se₂O.We show that local Coulomb correlations in the partially filled V 3d shells induce renormalizations of the DFT spectral functions close to the Fermi energy preserving their shape. These transformations are not accompanied by a spectral weight transfer to Hubbard bands, indicating a moderately correlated metallic state of bulk paramagnetic V₂Se₂O. The V 3d states exhibit a quasiparticle mass enhancement m∗/m ∼ 1.34 − 3.11 comparable to that in the isostructural compound V2Te2O. We demonstrate that orbital selectivity of correlation effects in V₂Se₂O is less pronounced compared to V2Te2O as can be traced from the weaker differentiation of m∗/m and local spin correlation functions for different V 3d orbitals. The analysis of the temperature dependence of the self-energy allows us to speculate on possible deviations from the Fermi-liquid behavior of V₂Se₂O.