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Quantifying uncertainties in crystal electric field Hamiltonian fits to neutron data

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 نشر من قبل Allen Scheie
 تاريخ النشر 2021
  مجال البحث فيزياء
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 تأليف Allen Scheie




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We systematically examine uncertainties from fitting rare earth single-ion crystal electric field (CEF) Hamiltonians to inelastic neutron scattering data. Using pyrochlore and delafossite structures as test cases, we find that uncertainty in CEF parameters can be large despite visually excellent fits. These results show Yb$^{3+}$ compounds have particularly large $g$-tensor uncertainty because of the few available peaks. In such cases, additional constraints are necessary for meaningful fits.



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