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arXiv · 1006.3988

Crystal field and magnetic structure of UO$_{2}$

Fei Zhou·Vidvuds Ozoliņš
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Abstract

The properties of UO$_{2}$ result from rich $f$-electron physics, including electronic Coulomb interactions, spin-orbit and crystal field effects, as well as inter-ionic multipolar coupling. We present a comprehensive theoretical study of the electronic structure of UO$_{2}$ using a combined application of self-consistent DFT+$U$ calculations and a model Hamiltonian. The $Γ_{5}$ ground state of U$^{4+}$ and the energies of crystal field excitations $Γ_{5} \rightarrow Γ_{3,4,1}$ are reproduced in very good agreement with experiment. We also investigate competing non-collinear magnetic structures and confirm 3-k as the T=0 K ground state magnetic structure of UO$_2$.

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Fei Zhou, Vidvuds Ozoliņš. 2011-01-12. Crystal field and magnetic structure of UO$_{2}$. https://doi.org/10.1103/physrevb.83.085106

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