Boulahya Khalid, Parras Marina, González-Calbet José María
Dpto. de Química Inorgánica, Facultad de Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain.
Chemistry. 2007;13(3):910-5. doi: 10.1002/chem.200600882.
Two new oxides of the Ruddlesden-Popper series have been isolated and structurally characterized in the Sr-Co-Ta-O system. X-ray and electron diffraction and high-resolution electron microscopy show that polycrystalline Sr(3)CoTaO(7) constitutes the n=2 member of a new Sr(n+1)(CoTa)(n)O(3n+1) homologous series, the essential feature of which is the existence of two connected Co/Ta octahedral layers, separated by Sr atoms. Sr(2)CoTaO(6), the n=infinity member of the series, shows a particular short-range ordering of Co and Ta at the octahedral sites leading, as shown by high-resolution electron microscopy, to the disordered intergrowth of simple and double perovskite type domains. Strategies to stabilize new oxides of this series are discussed.
在Sr-Co-Ta-O体系中已分离出两种Ruddlesden-Popper系列的新氧化物，并对其进行了结构表征。X射线和电子衍射以及高分辨率电子显微镜表明，多晶Sr(3)CoTaO(7)构成了新的Sr(n + 1)(CoTa)(n)O(3n + 1)同系物系列的n = 2成员，其基本特征是存在两个由Sr原子隔开的相连的Co/Ta八面体层。该系列的n = ∞成员Sr(2)CoTaO(6)在八面体位置显示出Co和Ta的特定短程有序，如高分辨率电子显微镜所示，导致简单和双钙钛矿型畴的无序共生。讨论了稳定该系列新氧化物的策略。
