磁場によって誘発されたフェリ磁気状態は,Co (II) イオンとキラル三重のBis (ニトロキシド) 基からなる分子ベースの磁石に含まれる
Youhei Numata1, Katsuya Inoue, Nikolai Baranov
1Department of Structural Molecular Science, The Graduate University for Advanced Studies, Okazaki 444-8585, Japan.
Journal of the American Chemical Society
|July 31, 2007
まとめ
この研究では,4つの異なる磁気状態を呈する新しい分子ベースの磁石[Co(hfac) ]BNO*を導入しています. そのキラル構造は,低温でのハードマグネット相を含むユニークな磁気特性につながります.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- マグネチズム (磁気) とは
背景:
- 分子ベースの磁石は,調節可能な特性を提供します.
- チラルの構造は,磁気秩序に影響を与えることができます.
- コバルト複合体は,磁気応用のために探求されています.
研究 の 目的:
- 新しい分子ベースの磁石[Co(hfac) ]を合成し,特徴づけ,BNO*.
- 結晶構造と磁気特性を研究する.
- 磁気状態の温度と磁場依存度を判定する.
主な方法:
- 構造分析のための単結晶X線 difraktion. 構造分析のための単結晶X線 difraktion.
- 温度に依存する磁気感受性測定.
- 同熱磁化曲線は,様々な温度と磁場において
主要な成果:
- 非中心対称のP1空間群におけるキラル一次元鎖の形成.
- 4つの磁性基底状態の観測:パラマグネティック,アンチフェロマグネティック,強制フェロマグネティック,フィールド誘発型変形性フェロマグネティック.
- 2 K で 25 kOe の強制場を持つ硬磁石の振る舞いの実証.
結論:
- キラルビス (((窒素酸化物)) リガンドはコバルト複合体においてユニークな磁気特性を誘導する.
- この材料は,温度と磁場によって引き起こされる複雑な磁気相変化を示しています.
- コバルトイオンのイシング特性により,変性磁気状態が安定し,硬い磁石の特性が生じる.
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