アニオン空白が誘発した磁気結晶アニソトロピーは,フッ素を添加した六角形コバルチートに含まれる
Olivier Mentré1, Houria Kabbour, Ghislaine Ehora
1Unité de Catalyse et de Chimie du Solide, CNRS UMR 8181, ENSC Lille - UST Lille, BP 90108, 59652 Villeneuve d'Ascq cedex, France.
Journal of the American Chemical Society
|March 16, 2010
まとめ
2つの新しいコバルト六角形ペロブスキートが合成され,特徴づけられました. フッ素の空白はコバルトイオンのスピン状態と向きに影響を与え,材料の性質に影響を与えます.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- クリスタログラフィーです.
背景:
- コバルト基六角ペロブスキットは,磁気および電子特性により興味を惹きます.
- 構造,電子構成,磁気行動の関係を理解することは,材料設計において極めて重要です.
研究 の 目的:
- 2つの新しいコバルト六角ペロフスキットを合成し,特徴づけること: 6H-Ba(6) Co(6) F(0.93) O(16) と10H-Ba(5) Co(5) F(0.77) O(12.88).
- フッ素の空白がこれらの材料の電子構造と磁気特性に与える影響を調査する.
主な方法:
- 構造分析のためのX線と中性子の difraktion.
- (19)F 固体核磁共振 (NMR) スペクトロスコーピー. 固体核磁共振 (NMR) スペクトロスコーピー.
- 磁気感受性と電気抵抗性の測定. 磁気感受性と電気抵抗性の測定.
- 密度関数理論 (DFT) と電子構造のための緊密結合計算.
主要な成果:
- 2つのペロフスキットの結晶構造が決定され,角を共有する四面体Co ((2) O ((7) ダイマーと面を共有する八面体オリゴーマーが明らかになった.
- 高いスピン Co(3+) を四面体サイトに,低いスピン Co(3+) / Co(4+) を八面体サイトに割り当て,電荷分布モデルが確立されました.
- [BaOF{1-x) ]層におけるフッ素の空白は,四面体二面体における重要な歪みを誘導し,Co{3+) イオンのスピン方向性を変化させます.
結論:
- この研究は,六角ペロフスキットにおけるコバルトイオンのスピン方向を調節する際に,フッ素の空白が果たす重要な役割を明らかにしている.
- この発見は,電子構造と磁気特性についての洞察を提供し,関連するコバルトオキシハリドとオキシヒドロキシドを設計するための基礎を提供します.
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