Synthesis and properties of a new quadruple perovskite: A-site ordered PbMn₃Mn₄O₁₂

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• 作者：T. Locherer^a ; R. Dinnebier^a ; R.K. Kremer^a ; M. Greenblatt^b ; ^{martha@rutchem.rutgers.edu} ; M. Jansen^a
• 关键词：PbMn3Mn4O12 ; A-site ordered quadruple perovskite ; Structure ; Magnetic and dielectric properties ; Multiferroic
• 刊名：Journal of Solid State Chemistry
• 出版年：2012
• 期刊代码：130_00224596
• 类别：ch
• 出版时间：June, 2012
• 卷：190
• 期：Complete
• 页码：277-284
• 文件大小：962 K

摘要

PbMn₃Mn₄O₁₂ a quadruple perovskite was prepared by high pressure and high temperature synthesis. Powder X-ray diffraction (PXD) and differential scanning calorimetry reveal a structural phase transition at 鈭?80 K. Rietveld refinement of the synchrotron room temperature data indicate rhombohedral symmetry (R-3) with a=6.43675(4) 脜 and 伪=109.556(2)掳. Similar 423 K PXD data refined in a body centered cubic cell (Im-3) with a=7.4283(9) 脜. The temperature variation of magnetization, shows a magnetic field dependent antiferromagnetic-like transition at 68 K, and dynamic fluctuations indicative of magnetic frustration. The semiconducting electrical behavior indicates a large decrease in the conductivity near 68 K. The temperature dependence of the real part of the dielectric constant, 蔚_real increases dramatically at 鈭?8 K, and shows relaxor-type ferroelectric behavior as a function of frequency. The intimate coupling of magnetic, electrical and dielectric properties at 68 K in PbMn₃Mn₄O₁₂ suggests possible multiferroic behavior.