A-Site-Ordered Perovskite MnCu3V4O12 with a 12-Coordinated Manganese(II)

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• 作者：Yasuhide Akizuki ; Ikuya Yamada ; Koji Fujita ; Norimasa Nishiyama ; Tetuo Irifune ; Takeshi Yajima ; Hiroshi Kageyama ; Katsuhisa Tanaka
• 刊名：Inorganic Chemistry
• 出版年：2013
• 出版时间：October 7, 2013
• 年：2013
• 卷：52
• 期：19
• 页码：11538-11543
• 全文大小：283K
• 年卷期：v.52,no.19(October 7, 2013)
• ISSN：1520-510X

文摘

A novel cubic perovskite MnCu₃V₄O₁₂ has been synthesized at a high pressure and high temperature of 12 GPa and 1373 K. This compound crystallizes in the A-site-ordered perovskite structure (space group Im3̅) with lattice constant a = 7.26684(10) 脜 at room temperature. The most notable feature of this compound lies in the fact that the Mn²⁺ ion is surrounded by 12 equidistant oxide ions to form a regular icosahedron; the situation of Mn²⁺ is unprecedented for the crystal chemistry of an oxide. An anomalously large atomic displacement parameter U_iso= 0.0222(8) 脜² is found for Mn²⁺ at room temperature, indicating that the thermal oscillation of the small Mn²⁺ ion in a large icosahedron is fairly active. Magnetic susceptibility and electric resistivity measurements reveal that 3d electrons of Mn²⁺ ions are mainly localized, while 3d electrons in Cu²⁺ and V⁴⁺ ions are delocalized and contribute to the metallic conduction.