Martel Laura, Naji Mohamed, Popa Karin, Vigier Jean-François, Somers Joseph
European Commission, DG Joint Research Centre-JRC, Directorate G - Nuclear Safety and Security, Postfach 2340, D-76125, Karlsruhe, Germany.
Sci Rep. 2017 Sep 25;7(1):12269. doi: 10.1038/s41598-017-12544-8.
The detailed characterization of local order and disorder in isometric ABO crystalline pyrochlores is of significant importance in view of their wide range and sensitive technological applications. Nevertheless, much remains to be understood concerning their atomic scale structures. Here we specifically pinpoint local order and disorder in four stoichiometric LnZrO (Ln = La, Nd, Sm and Eu) pyrochlores using a combination of three standard easily available laboratory techniques: XRD, O solid-state MAS NMR and Raman spectroscopy. The evolution of the oxygen sub-lattice identifies specific features (extra O NMR signals and Raman bands) which undoubtedly reveal local oxygen order and disorder in these stoichiometric long range ordered crystalline pyrochlores. These results complete the understanding of the atomic scale in these stoichiometric pyrochlores necessitating the need for new microscopic structural models.
鉴于等轴晶系ABO型晶体焦绿石具有广泛且敏感的技术应用，详细表征其局部有序和无序状态具有重要意义。然而，关于它们的原子尺度结构仍有许多有待了解之处。在此，我们结合三种标准且易于获得的实验室技术：X射线衍射（XRD）、氧固体高分辨魔角旋转核磁共振（O 固体高分辨魔角旋转核磁共振）和拉曼光谱，具体确定了四种化学计量比的LnZrO（Ln = La、Nd、Sm和Eu）焦绿石中的局部有序和无序情况。氧亚晶格的演变确定了特定特征（额外的O核磁共振信号和拉曼谱带），这些特征无疑揭示了这些化学计量比的长程有序晶体焦绿石中的局部氧有序和无序情况。这些结果完善了对这些化学计量比焦绿石原子尺度的理解，因此需要新的微观结构模型。
