New Type of Charge/Orbital Ordering above Room Temperature in the Perovskite Bi2/3Sr1/3MnO3

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• 作者：M. Hervieu ; S. Malo ; O. Perez ; P. Ber&agrave ; n ; C. Martin ; G. Baldinozzi ; and B. Raveau
• 刊名：Chemistry of Materials
• 出版年：2003
• 出版时间：January 28, 2003
• 年：2003
• 卷：15
• 期：2
• 页码：523 - 527
• 全文大小：285K
• 年卷期：v.15,no.2(January 28, 2003)
• ISSN：1520-5002

文摘

A new type of charge ordering stable up to T₁ ges/entities/ap.gif"> 500 K has been evidenced by electronmicroscopy in the Mn³⁺-rich perovskite Bi_2/3Sr_1/3MnO₃. This new superstructure, based ona Imma-type subcell is characterized by a double modulation with a = 2a_pgif">, b = 4a_p, c =a_pgif">. X-ray powder diffraction evidences a second structural transition at T₂ ges/entities/ap.gif"> 580 K andsuggests a displacive modulation of the oxygen atoms below T₂. These results are interpretedas the correlated coexistence of charge-orbital ordering and modulated displacive orderingof oxygen atoms, in the form of double Mn stripes, below 500 K.