Coulomb (or Strong) Correlation Effects in the Band Structure of Eu₂O₃

Abstract

Two band-structure calculations of Eu,O, are performed, one of them in the metallic phase and the other in the semiconducting phase; the difference between the corresponding band Hamiltonians is the occupation potential U(T) that includes the Coulomb correlation effects. In both phases, the 4f occupied bands are mixed with the 2p bands; this fact broadens these 4f bands so that its calculation is possible in this complex crystal lattice Ti. In the semiconducting band structure, the 4f empty bands are localized in the d-zone energy showing (4f, 5d) hybridization that produces a broadening still greater than for the 4f occupied bands. The semiconducting gap is I ? : -H i and its value is 3.7 eV.On a realis6 deux calculs de la structure des bandes du compost5 Eu,O,: l'un correspondant Q la phase mbtallique et l'autre B la phase semiconductrice. La diffhrence des calculs se traduit par l'addition du potentiel d'occupation ( U(T) que tient compte des effects de correlation coulombienne. On trouve que les bandes occupkes 4f sont melanghs avec les Btats 2p, ce qui produit un Blargissement des bandes 4f,qu'on a pu B calculer. De mbme, dans le calcul de la phase semiconductrice on trouve les Btats 4f hybrides avec les 6tats 5d, ce qui produit un Blargissement des Btats 4f plus important qui cklui correspondant aux Btats de la bande de valence. La gap du semiconducteur c'est 3,7 eV et correspond & la transition I ? : -Hi.

Renormalized Atom Model (RAM) Applied to the Heavy Rare‐Earth Sesquioxides in Cubic Crystal Structure

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A First‐Principles Pseudopotential Model for the Strong Intrasite Interaction Applied to the 4f13 Configuration (Yb2O3)

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Electronic properties of EuO and Eu2O3: FP-LAPW and LCAO computations and Compton spectroscopy strategies

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