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Incommensurate Charge Order Phase in Fe2OBO3 due to Geometrical Frustration

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 نشر من قبل Manuel Angst
 تاريخ النشر 2007
  مجال البحث فيزياء
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The temperature dependence of charge order in Fe2OBO3 was investigated by resistivity and differential scanning calorimetry measurements, Mossbauer spectroscopy, and synchrotron x-ray scattering, revealing an intermediate phase between room temperature and 340 K, characterized by coexisting mobile and immobile carriers, and by incommensurate superstructure modulations with temperature-dependent propagation vector (1/2,0,tau). The incommensurate modulations arise from specific anti-phase boundaries with low energy cost due to geometrical charge frustration.



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