一次元のコバルト・ラジカル・コーディネーション・マグネットにおける巨大な強制力
Norio Ishii1, Yoshitomo Okamura, Susumu Chiba
1Department of Applied Physics and Chemistry and Course of Coherent Optical Science, The University of Electro-Communications, Chofu, Tokyo 182-8585, Japan. ishi@pc.uec.ac.jp
Journal of the American Chemical Society
|December 14, 2007
まとめ
新しい金属根ポリマーは,これまでに記録された最も高い強制力を発揮し,低温でも非常に硬い磁石として機能します. しかし,その磁気特性は,磁気化の急速な変化により,10K以上で柔らかく変化します.
科学分野:
- 材料科学 材料科学とは
- マグネチズム (磁気) とは
- ポリマー化学のポリマー化学について
背景:
- 先進的な磁気材料の開発は,技術革新にとって極めて重要です.
- メタル・ラジカルポリマーは,ペアリングされていない電子のスピンにより,ユニークな磁気特性を有しています.
- 磁気行動の温度依存を理解することは,材料の応用の鍵です.
研究 の 目的:
- 新しい金属根ポリマーを合成し,特徴づけること.
- 合成されたポリマーの磁気特性,特に強制力を調査する.
- 温度に依存する磁気行動と磁気化ダイナミクスを探求する.
主な方法:
- コバルト ((II) ビス (((ヘクサフッロアセチラセトネート)) -ビス (((ピリジル)) ニトロニル-ニトロキシドのリジカルポリマー ([Co (((hfac) 2.BPNN)) の合成.
- ハイステレシスループを含む磁気特性の測定で強制場を決定する.
- 温度に依存する磁気感受性および磁気化に関する研究.
主要な成果:
- メタル・ラジカルポリマー [Co(hfac) 2.BPNN]は6Kで52kOe (4.1MA m-1) の強迫力場を記録した.
- この例外的な強制力は,この材料をこれまでに報告された中で最も硬い磁石として分類する.
- 10K以上では,この材料は,高速磁化方向転換のダイナミクスに起因する柔らかい磁気特性を示した.
結論:
- 合成された金属根ポリマーは,硬磁性材料の重要な進歩を表しています.
- 硬い磁気から柔らかい磁気への温度依存の移行は,磁気状態のダイナミックな性質を強調しています.
- 磁気化ダイナミクスの制御に関するさらなる研究は,磁気貯蔵とスピントロニクスにおける新たな応用につながる可能性があります.
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