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Magnetic phase transitions in SmCoAsO

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 نشر من قبل Veer Awana Dr
 تاريخ النشر 2010
  مجال البحث فيزياء
والبحث باللغة English
 تأليف V.P.S. Awana




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Magnetization, x-ray diffraction and specific-heat measurements reveal that SmCoAsO undergoes three magnetic phase transitions. A ferromagnetic transition attributed to the Co ions, emerges at TC=57 K with a small saturation moment of 0.15muB/Co. Reorientation of the Co moment to an antiferromagnetic state is obtained at TN2=45 K. The relative high paramagnetic effective moment Peff=1.57 MuB/Co indicates an itinerant ferromagnetic state of the Co sublattice. The third magnetic transition at TN1=5 K is observed clearly in the specific-heat study only. Both magnetic and 57Fe Mossbauer studies show that substitution of small quantities of Fe for Co was unsuccessful.



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