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arXiv · 1006.2351

Structural Features of Layered Iron Pnictide Oxides (Fe2As2)(Sr4M2O6)

H. Ogino·S. Sato·Y. Matsumura·N. Kawaguchi·K. Ushiyama·Y. Katsura·S. Horii·K. Kishio·J. Shimoyama
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Abstract

Structural features of newly found perovskite-based iron pnictide oxide system have been systematically studied. Compared to REFePnO system, perovskite-based system tend to have lower Pn-Fe-Pn angle and higher pnictogen height owing to low electronegativity of alkaline earth metal and small repulsive force between pnictogen and oxygen atoms. As-Fe-As angles of (Fe2As2)(Sr4Cr2O6), (Fe2As2)(Sr4V2O6) and (Fe2Pn2)(Sr4MgTiO6) are close to ideal tetrahedron and those pnictogen heights of about 1.40 A are close to NdFeAsO with optimized carrier concentration. These structural features of this system may leads to realization of high Tc superconductivity.

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H. Ogino, S. Sato, Y. Matsumura, N. Kawaguchi, K. Ushiyama, Y. Katsura, S. Horii, K. Kishio, J. Shimoyama. 2010-06-11. Structural Features of Layered Iron Pnictide Oxides (Fe2As2)(Sr4M2O6). https://doi.org/10.1016/j.physc.2009.10.099

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