トンネル構造における相応のカチオンと電荷調節をカップリングした,Na{0.40{2)) MnO{2)
Izabela Kruk1, Pawel Zajdel, Wouter van Beek
1NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.
Journal of the American Chemical Society
|August 2, 2011
まとめ
ナトリウム・マンガン酸化物 (Na{0.40{2}) MnO{2}) は,310 K未満の複雑なナトリウムとマンガンの順序を示している.この研究は,その多孔な酸化物構造内のNa位置とMnバレンスのカップリングされた変調を明らかにしている.
科学分野:
- 材料科学 材料科学とは
- 固体化学 固体化学
- クリスタログラフィーです.
背景:
- Na{0.40}{2}) MnO{2}は,混合のMn{3+) とMn{4+) のバレンスを有する多孔性酸化物です.
- この材料には,八面体と正方形ピラミッド形のマンガンと酸素の調整単位が含まれています.
- 構造的および電子的なオーダーリングの理解は,その潜在的なアプリケーションにとって極めて重要です.
研究 の 目的:
- Na{0.40{2}) MnO{2} での構造的および電子的なオーダーリング現象を調査する.
- ナトリウムとマンガンの順序転換の性質を決定する.
- ナトリウム順序とマンガンの値位状態の関係を解明する.
主な方法:
- ニュートロン difraktion 研究. ニュートロン difraktion 研究.
- シンクロトロンX線 difraktion研究. シンクロトロンX線 difraktion研究.
- クリスタル構造と対称性の変化の分析.
主要な成果:
- 約310K (T(Na)) で発生するナトリウム順序の識別.
- マンガンイオンの結合電荷と軌道順序の証拠.
- T以下では,Pbam構造はPnnm対称性の (ab 4c) スーパーセルに変形する.
- Na位置/占有率とMnバレンスを含むc軸チャネルに沿った相応変調が観察されました.
結論:
- Na{0.40}2)) MnO{2) は,複合的で結合された秩序現象を示している.
- ナトリウム順序とマンガンのバレンスの相互作用は,結晶構造に大きな影響を与えます.
- この発見は,関連する多孔性マンガネス酸化物の構造-特性関係に関する洞察を提供します.
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