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arXiv · 0909.3998

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

R. Klingeler·L. Wang·U. Kohler·G. Behr·C. Hess·B. Buchner
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Abstract

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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R. Klingeler, L. Wang, U. Kohler, G. Behr, C. Hess, B. Buchner. 2009-09-22. Thermal expansion of RFeAsO (R=La,Ce,Pr,Sm,Gd). https://doi.org/10.1088/1742-6596/200/1/012088

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