Breakdown of Hund's rule for CuFeAs

@article{Song2021BreakdownOH,
  title={Breakdown of Hund's rule for CuFeAs},
  author={Zeyi Song and Xiuguang Jiang and Xiao-Fang Ouyang and Yu-Zhong Zhang},
  journal={Physical Review B},
  year={2021}
}
The ground-state properties of CuFeAs were investigated by applying density functional theory calculations within the generalized gradient approximation (GGA) and $\mathrm{GGA}+U$. We find that the bicollinear antiferromagnetic state with antiparallel orbital magnetic moments on each iron which violates the Hund's rule is favored by the on-site Coulomb interaction, which is further stabilized by Cu vacancy. The magnetic ground state can be used to understand weak antiferromagnetism in CuFeAs… 

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