The properties of UO2 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 UO2 using a combined application of self-consistent DFT+U calculations and a model Hamiltonian. The Γ5 ground state of U4+ and the energies of crystal field excitations Γ5→Γ3,4,1 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 UO2.
@article{arxiv.1006.3988,
title = {Crystal field and magnetic structure of UO$_{2}$},
author = {Fei Zhou and Vidvuds Ozoliņš},
journal= {arXiv preprint arXiv:1006.3988},
year = {2015}
}