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Thermal expansion of RFeAsO (R=La,Ce,Pr,Sm,Gd)

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 نشر من قبل Ruediger Klingeler
 تاريخ النشر 2009
  مجال البحث فيزياء
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We present measurements of the thermal expansion coefficient $alpha$ of polycrystalline RFeAsO (R = La,Ce,Pr,Sm,Gd). Anomalies at the magnetic ordering transitions indicate a significant magneto-elastic coupling and a negative pressure dependence of $T_{rm N}$ . The structural transitions are associated by large anomalies in $alpha$. Rare earth magnetic ordering in CeFeAsO, PrFeAsO, and SmFeAsO yields large positive anomalies at low temperatures.



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