Inverse Charge Transfer in the Quadruple Perovskite CaCu3Fe4O12

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• 作者：Ikuya Yamada ; Makoto Murakami ; Naoaki Hayashi ; Shigeo Mori
• 刊名：Inorganic Chemistry
• 出版年：2016
• 出版时间：February 15, 2016
• 年：2016
• 卷：55
• 期：4
• 页码：1715-1719
• 全文大小：316K
• ISSN：1520-510X

文摘

Structural and spectroscopic analyses revealed that the quadruple perovskite CaCu₃Fe₄O₁₂ undergoes an “inverse” electron charge transfer in which valence electrons move from B-site Fe to A′-site Cu ions (∼3Cu^∼2.4+ + 4Fe^∼3.65+ → ∼3Cu^∼2.2+ + 4Fe^∼3.8+) simultaneously with a charge disproportionation transition (4Fe^∼3.8+ → ∼2.4Fe³⁺ + ∼1.6Fe⁵⁺), on cooling below 210 K. The direction of the charge transfer for CaCu₃Fe₄O₁₂ is opposite to those reported for other perovskite oxides such as BiNiO₃ and ACu₃Fe₄O₁₂ (A = Sr²⁺ or the large trivalent rare-earth metal ions), in which the electrons move from A/A′-site to B-site ions. This finding sheds a light on a new aspect in intermetallic phenomena for complex transition metal compounds.