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arXiv · 1004.1340

Lattice anomalies in the FeAs$_{\rm 4}$ tetrahedra of the NdFeAsO$_{\rm 0.85}$ superconductor that disappear at T$_{\rm c}$

M. Calamiotou·I. Margiolaki·A. Gantis·E. Siranidi·Z. A. Ren·Z. X. Zhao·E. Liarokapis
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Abstract

High resolution synchrotron X-ray powder diffraction (SXRPD) was used to study the temperature dependence of the oxygen deficient NdFeAsO$_{0.85}$ superconducting compound. By employing a dense temperature sampling we have managed to reveal unnoticed structural modifications that start around $\sim$180K, and disappear at the transition temperature. The data show minor changes of the structural characteristics in the Nd-O charge reservoir layer while in the superconducting Fe-As layer the FeAs$_{4}$ tetrahedron shows gradual modifications below $\sim$180K, which suddenly disappear at T$_{\rm c}$ strongly indicating a connection with superconductivity.

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M. Calamiotou, I. Margiolaki, A. Gantis, E. Siranidi, Z. A. Ren, Z. X. Zhao, E. Liarokapis. 2010-12-07. Lattice anomalies in the FeAs$_{\rm 4}$ tetrahedra of the NdFeAsO$_{\rm 0.85}$ superconductor that disappear at T$_{\rm c}$. https://doi.org/10.1209/0295-5075%2F91%2F57005

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