フルレンベースのフェロマグネット Eu3C70とEu9C70の合成,構造,磁気特性
Taishi Takenobu1, Dam H Chi, Serena Margadonna
1Institute for Materials Research, Tohoku University, Katahira, Sendai 980-8577, Japan.
Journal of the American Chemical Society
|February 13, 2003
まとめ
ユーロピウムのC(70) フラーレンへのインターカレーションにより,2つの磁性化合物:反鉄磁石と鉄磁石が得られます. フェロマグネットは,バイナリ・エウロピウム磁石と同等である38Kの移行温度を示しています.
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
- 化学 化学は化学です.
背景:
- C ((70) のようなフルレーンは,ゲスト原子を宿し,新しい材料の性質をもたらすことができます.
- ユーロピウム (Eu) は,磁気特性,特に二価状態 (Eu(2+)) で知られている希土元素です.
研究 の 目的:
- ユーロピウムをC(70) フルレネにインターカレートすることによって形成される磁性化合物を合成し,特徴づけること.
- これらの新しいエウロピウム-炭素化合物の磁気特性と結晶構造を調査する.
主な方法:
- ヨーロッパのインターケラC ((70)) 化合物の合成.
- 磁気順序と移行温度を決定するための磁気感受性測定.
- クリスタル構造を分析するためのX線 difraktion.
主要な成果:
- 2つの磁性化合物が合成されました: Eu(x) C(70) (x ≈ 3) が傾いた反鉄磁石 (T(C) = 5 K) として,Eu(x) C(70) (x ≈ 9) が鉄磁石 (T(C) = 38 K) として.
- この2つの化合物は,Eu(2+) イオンと一致する磁気行動を示す.
- 鉄磁気 Eu{9-δ) C{70) は,fcc構造の八面体孔に Eu{2+) の立方体群集を特徴としています.
- Eu{9-δ) C{70) の高い移行温度は,短距離の Eu{2+) - Eu{2+) と高い調整数によるものである.
結論:
- ユーロピウムのC ((70) へのインターケレーションにより,調節可能な性質を持つ新しい磁気材料が生成されます.
- フルレンの宿主の構造は,磁気相互作用と移行温度に大きな影響を与えます.
- ユーロピウムインターケラフルレンは,磁気材料として有望であり,低温磁気における応用の可能性があります.
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