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The nuclear quadrupole moment of 57Fe from microscopic nuclear and atomic calculations

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 نشر من قبل Gabriel Martinez-Pinedo
 تاريخ النشر 2001
  مجال البحث فيزياء
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The nuclear quadrupole moment of the I=3/2- excited nuclear state of 57Fe at 14.41 keV, important in Mossbauer spectroscopy, is determined from the large-scale nuclear shell-model calculations for 57Fe and also from the electronic ab initio and density functional theory calculations including solid state and electron correlation effects for the molecules Fe(CO)_5 and Fe(C_5 H_5)_2. Both independent methods yield very similar results. The recommended value is 0.16(1) eb. The NQM of the isomeric 10+ in 54Fe has also been calculated. The new value (0.5 eb), consistent with the perturbed angular distribution data, is by a factor of two larger than the currently recommended value.



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