New iron-based arsenide oxides (Fe2As2)(Sr4M2O6)(M = Sc, Cr)
New iron-based arsenide oxides (Fe2As2)(Sr4M2O6)(M = Sc, Cr)
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DOI：
10.1088/0953-2048/22/8/085001
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发表时间：
2009-08-01
影响因子：
3.6
通讯作者：
Shimoyama, Jun-ichi
中科院分区：
文献类型：
--
作者：
Ogino, Hiraku;Katsura, Yukari;Shimoyama, Jun-ichi
发现了新的砷氧化物（Fe_2As_2）（Sr_4 M_2 O_6）（M = Sc，Cr：M ~（-22426））。这些材料与我们以前研究中发现的（Fe_2P_2）（Sr_4Sc_2O_6）是同构的。新化合物为四方晶系，空间群为P4/nmm，由反氟石型FeAs层和钙钛矿型阻挡层组成。这些化合物具有对应于c轴长度的长的层间Fe-Fe距离; Sc-22426中的15.8埃是铁基磷属元素化物氧化物系统中最长的。用含铬（Fe_2As_2）（Sr_4Cr_2O_6）化合物研究了该体系中钙钛矿结构的化学柔性。不同的趋势被发现在键角和键长的新磷属元素化物氧化物相比，报告的系统，如REFePnO。在这些化合物中没有超导性被认为是由于在未掺杂的REFeAsO的情况下，载流子浓度不足。
We have discovered new arsenide oxides (Fe2As2)(Sr4M2O6) (M = Sc, Cr: M-22426). These materials are isostructural with (Fe2P2)(Sr4Sc2O6), which was found in our previous study. The new compounds are tetragonal with a space group of P4/nmm and consist of the anti-fluorite-type FeAs layer and a perovskite-type blocking layer. These compounds have long interlayer Fe-Fe distances corresponding to the c-axis length; the 15.8 angstrom in Sc-22426 is the longest in the iron-based pnictide oxide systems. Chemical flexibility of the perovskite block in this system was probed by chromium-containing (Fe2As2)(Sr4Cr2O6). Different trends were found in bond angle and bond length of the new pnictide oxides compared to the reported systems, such as REFePnO. The absence of superconductivity in these compounds is considered to be due to insufficient carrier concentration as in the case of undoped REFeAsO.