BiMnO (((3+デルタ) の結晶と磁気構造と特性
Alexei A Belik1, Katsuaki Kodama, Naoki Igawa
1International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan. Alexei.BELIK@nims.go.jp
Journal of the American Chemical Society
|May 22, 2010
まとめ
ビスムートマンガニート (BiMnO3+デルタ) の結晶と磁気構造は,中性子 difraktion を用いて決定した. 酸素含有量 (デルタ) は,結晶の対称性,磁気順序,磁気モメントの大きさに影響し,BiMnO ((3.14) はスピンガラス状態を示す.
科学分野:
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
- クリスタルグラフィーです.
- マグネチズム (磁気) とは
背景:
- ビスマスマンガニット (BiMnO(3+デルタ)) は,複雑な結晶と磁気構造を持つ材料です.
- ペロブスキートマンガニートの性質は,酸素ステキオメトリーと欠陥に対して敏感であることが知られている.
研究 の 目的:
- 異なる酸素含有量 (デルタ=0.03,0.08,0.14) に対してBiMnOの結晶と磁気構造を決定する.
- 構造的対称性,磁気順序,磁気モメントに対する酸素ステキオメトリーの影響を調査する.
- BiMnO (((3+デルタ)) の性質を,関連するランタンマンガニット (LaMnO (((3+デルタ)) の性質と比較する.
主な方法:
- 低温 (8-10 K) と室温 (290 K) で収集された中性子 difraktion データのリートヴェルド精製.
- スペースグループ決定と格子パラメータを含む結晶構造の分析.
- 磁気構造,磁気配列温度 (T~C) と精錬された磁気モメントの決定.
主要な成果:
- BiMnO ((3.03)) とBiMnO ((3.08) は,モノクリニック系 (C2/c,P2 ((1) /c) に結晶し,それぞれ82K以下と68K以下でフェロマグネティズムを示し,磁気モーメントは10Kで2.88 ((2) μBと2.33 ((2) μBである.
- Mnの空白は特定の場所に位置し,結晶の対称性における観測された変化を潜在的に誘導しています.
- BiMnO(3.14) は,オーソロンビック系 (Pnma) で結晶化し,8Kまで磁気順序がなく,スピンガラスの磁気状態を示します.
結論:
- BiMnO ((3+デルタ) の結晶構造,磁気順序,磁気性質の体系的な変化は,酸素含有量 (デルタ) に強く依存しています.
- 求人注文と料金注文は,観察された構造的移行のメカニズムとして提案されています.
- この研究は,BiMnO ((3+デルタ) の詳細な構造および磁気特性を提供し,酸素ステキオメトリーによる調整性を強調しています.
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