JETP Letters: issues online

The effect of Coulomb correlations on the electronic structure of bulk van der Waals material V₂Te₂O is studied by the charge self-consistent density functional theory and dynamical mean-field theory method. Our results show a significant correlation-induced renormalization of the spectral functions in the vicinity of the Fermi energy which is not accompanied by a transfer of the spectral weight to Hubbard bands. The computed quasiparticle effective mass enhancement m^*/m for the V 3d states varies from 1.31 to 3.32 indicating an orbital-dependent nature of correlation effects and suggests an orbital-selective formation of local moments in the V 3d shell. We demonstrate that taking into account of Coulomb interaction between the V 3d electrons yields the electronic specific heat coefficient γ = 26.94 mJ K^-2 mol^-1 in reasonable agreement with the experiment. We show that the strength of Coulomb correlations is sufficient to trigger a band shift along the Z-Γ-X path of the Brillouin zone leading to a collapse of the electronic Fermi surface pocket centered on the Γ-Z direction predicted by density functional theory.