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Crystal Field Levels and Magnetic Anisotropy in the Kagome Compounds $rm{Nd_3Sb_3Mg_2O_{14}}$, $rm{Nd_3Sb_3Zn_2O_{14}}$, and $rm{Pr_3Sb_3Mg_2O_{14}}$

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 نشر من قبل Allen Scheie
 تاريخ النشر 2018
  مجال البحث فيزياء
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We report the crystal field levels of several newly-discovered rare-earth kagome compounds: $rm{Nd_3Sb_3Mg_2O_{14}}$, $rm{Nd_3Sb_3Zn_2O_{14}}$, and $rm{Pr_3Sb_3Mg_2O_{14}}$. We determine the CEF Hamiltonian by fitting to neutron scattering data using a point-charge Hamiltonian as an intermediate fitting step. The fitted Hamiltonians accurately reproduce bulk susceptibility measurements, and the results indicate easy-axis ground state doublets for $rm{Nd_3Sb_3Mg_2O_{14}}$ and $rm{Nd_3Sb_3Zn_2O_{14}}$, and a singlet ground state for $rm{Pr_3Sb_3Mg_2O_{14}}$. These results provide the groundwork for future investigations of these compounds and a template for CEF analysis of other low-symmetry materials.

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