Search

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 .