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Abstract Correlated band theory implemented as a combination of the relativistic density functional theory with exact diagonalization [DFT+U(ED)] of the Anderson impurity term with Coulomb repulsion U in the 5f shell is applied to the magnetic field polarized state of $$\hbox {UTe}_2$$ . We demonstrate that the DFT+U(ED) approach provides a good agreement with very recent x-ray absorbtion near edge structure (XANES) and x-ray magnetic circular dichroism (XMCD) experiments. The branching ratio for the $$M_{4,5}$$ edge transitions of uranium, and the valence spin-orbit interaction per hole were evaluated in a perfect agreement with the XANES. The orbital-to-spin moment ratio is calculated with DFT+U(ED) within the range of values extracted from XMCD data. The uranium atom 5f-shell ground state with 33 $$\%$$ of $$f^2$$ and 58 $$\%$$ of $$f^3$$ configurations is determined. Both XMCD and DFT+U(ED) point out the intermediate valence of uranium as well as itinerant-localized dichotomy in $$\hbox {UTe}_2$$ .

Abstract The electronic structure, spin and orbital magnetic moments, and the magnetic anisotropy energy in selected U-based compounds are investigated making use of the correlated band theory. First, we demonstrate that the LSDA+U approach with exact atomic limit implemented as a combination of the relativistic density functional theory with the Anderson impurity model provides a good quantitative description for UGa $${}_2$$ 2 . Further, the method is applied to UFe $$_{12}$$ 12 and UFe $${}_{10}$$ 10 Si $${}_2$$ 2 ferromagnets. The calculated positive uniaxial magnetic anisotropy together with negative enthalpy of formation for UFe $${}_{10}$$ 10 Si $${}_2$$ 2 make it as a candidate for the magnetically hard materials. Our studies suggest a viable route for further development of the rare-earth-lean permanent magnets by replacing a part of U atoms by some rare-earth like Sm in UFe $${}_{10}$$ 10 Si $${}_2$$ 2 .

We theoretically investigate the electronic and magnetic structure of Fe 2 Hf. The density functional theory calculations are shown to produce the negative, easy-plane, magnetic anisotropy in the hexagonal Fe 2 Hf. Antimony substitution suppresses the planar magnetization direction and favors the uniaxial magnetic anisotropy, in agreement with experimental observations. Our study suggests the possibility of the chemical control of the magnetic anisotropy in Fe 2 Hf by Sb substitution, and illustrates the potential of (Fe,Sb) 2 + x Hf 1 − x Laves phase alloys for the permanent magnet applications.