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arXiv · 0808.1024

Tetragonal to orthorhombic phase transition in SmFeAsO: a synchrotron powder diffraction investigation

A. Martinelli·A. Palenzona·C. Ferdeghini·M. Putti·E. Emerich
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Abstract

The crystal structure of SmFeAsO has been investigated by means of Rietveld refinement of high resolution synchrotron powder diffraction data collected at 300 K and 100 K. The compound crystallizes in the tetragonal P4/nmm space group at 300 K and in the orthorhombic Cmma space group at 100 K; attempts to refine the low temperature data in the monoclinic P112/n space group diverged. On the basis of both resistive and magnetic analyses the tetragonal to orthorhombic phase transition can be located at T about 140 K.

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A. Martinelli, A. Palenzona, C. Ferdeghini, M. Putti, E. Emerich. 2008-08-07. Tetragonal to orthorhombic phase transition in SmFeAsO: a synchrotron powder diffraction investigation. https://doi.org/10.1016/j.jallcom.2008.10.153

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