La_1/2Sr_3/2MnO₄的制备以及非公度电荷有序和轨道电子有序

La 1/2 Sr 3/2 MnO 4 的制备以及非公度电荷有序和轨道电子有序 Synthesis of and Incommensurate Charge and Orbital Ordering in La 1/2 Sr 3/2 MnO 4 Layered Perovskite 方频捷 1 2 3 first-author 桂嘉年 1 2 3 何佳清 1 2 3 朱波 1 2 3 王仁卉 1 2 3 赵东山 1 2 3 武汉大学物理科学与技术学院 武汉大学物理科学与技术学院 郑州大学材料研究中心,湖北,武汉,430072 郑州大学材料研究中心,湖北,武汉,430072 430072中国科学院北,湖北,武汉 430072中国科学院北,湖北,武汉 用固态反应法制备了La1/2Sr3/2MnO4相.X射线能谱分析证实了样品的平均成分为La0.45Sr1.49-MnO4,且有一定的微观成分不均匀性.用透射电镜在100K低温下观察到了[001]带轴电子衍射花样中出现的超衍射斑点,它来源于非公度电荷有序和轨道电子有序,其非公度调制矢量为k=δ[110]T*,其中δ=0.19.经分析,这种δ=0.19的非公度调制是δ=1/4和δ=1/6的公度调制无规分布的结果. Polycrystalline bulky samples of La1/2Sr3/2MnO4 were systhesized by conventional solid-state reaction in air. Composition analysis by energy dispersive X-ray spectrometer indicated that the average composition of the sample is La0.45 Sr1.49 MnO4 with a minor fluctuation. The [001] zone-axis electron diffraction patterns taken at about 100 K revealed the presence of superlattice peaks, due to the incommensurate charge and orbital ordering. The incommensurate modulation wave vector is k = δ[110]T*, with δ = 0. 19. Such an incommensurate modulation may be described as a random distribution of two commensurate modulations with δ= 1/4 and 1/6. La1/2Sr3/2 MnO4钙钛矿 电子衍射 非公度调制 电荷有序 轨道电子有序 La1/2 Sr3/2 MnO4 perovskite electron diffraction incommensurate modulation charge ordering orbital ordering O766 国家自然科学基金资助项目（9974031） 2002-03-01 2021-04-01 3