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arXiv · 0903.5484

Structure and Physical properties of New layered oxypnictides $Sr_4Sc_2O_6M_2As_2$ (M=Fe and Co)

Y. L. Xie·R. H. Liu·T. Wu·G. Wu·Y. A. Song·D. Tan·X. F. Wang·H. Chen·J. J. Ying·Y. J. Yan·Q. J. Li·X. H. Chen
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Abstract

We have successfully prepared the new layered oxypnictides $Sr_4Sc_2O_6M_2As_2$ (M=Fe and Co). They adopt the tetragonal structure, being the same as that of $Sr_4Sc_2O_6Fe_2P_2$. The lattice constants are a=0.4045 nm and c= 0.5802 nm for M=Fe, and a=0.4045 nm and c=1.5695 nm for M=Co, respectively. Their transport and magnetic properties have been systematically studied. The temperature dependence of Hall coefficient and thermoelectric powder for $Sr_4Sc_2O_6Fe_2As_2$ compound show complicated behavior, similar to that of iron-based parent compounds LnOFeAs and $BaFe_2As_2$. It suggests that the $Sr_4Sc_2O_6Fe_2As_2$ could be considered a new parent compound as iron-based superconductors.

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Y. L. Xie, R. H. Liu, T. Wu, G. Wu, Y. A. Song, D. Tan, X. F. Wang, H. Chen, J. J. Ying, Y. J. Yan, Q. J. Li, X. H. Chen. 2009-03-31. Structure and Physical properties of New layered oxypnictides $Sr_4Sc_2O_6M_2As_2$ (M=Fe and Co). https://doi.org/10.1209/0295-5075/86/57007

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