ディスプロシウム (III) ビスプロリド) 複合体の強い軸性により,65 Kの磁気阻害が発生する
Alexandre H Vincent1, Yasmin L Whyatt2, Nicholas F Chilton2
1Department of Chemistry, University of California, Berkeley, Berkeley, California94720, United States.
Journal of the American Chemical Society
|January 11, 2023
まとめ
研究者らは,高性能の単分子磁石として機能する新しいディスプロシウム化合物[K(18-crown-6) ][Dy(BC4Ph5) 2を開発した. この材料は65Kまでの磁気メモリを示し,既存のディスプロシウムベースの磁石を上回ります.
科学分野:
- 協調化学
- 材料科学
- マグネティズム
背景:
- 置換されたディスプロソセニウム複合体は,強力な軸性リガンド場があるため,単分子磁石 (SMM) として知られています.
- 強化された軸性を持つSMMの開発は,より高い動作温度を達成し,磁気メモリを維持する鍵です.
研究 の 目的:
- 新しいディスプロシウムビス (ボロリド) 化合物を合成し,特徴づけるために,[K18-crown-6) ][DyBC4Ph52] (1).
- 単一分子磁石としての性能を評価し,既存のディスプロソセニウム類と比較する.
主な方法:
- ディスプロシウムビス (ボロリド) 複合体の合成と特徴付け.
- 磁気ヒステレシスを評価するための変形磁場測定.
- リラクゼーションダイナミクスを決定するAC磁気感受性研究 (オルバッハ,ラマン,量子トンネリング).
- 理論的検証のためのスピンダイナミクスの計算.
主要な成果:
- コンパウンド1は66Kまでのオープン磁気ヒステリシスを示し,それを最高性能のSMMとして識別します.
- ディスプロシウムベースのSMMの最高値の1つである65Kの100秒のブロック温度が記録されました.
- 実験のリラクゼーションパラメータ (Ueff = 1500 〜 100 センチメートル−1, τ0 = 10−12.0 〜 9 秒) は理論的な計算によって確認された.
結論:
- ディスプロシウムビス (ボロリド) 化合物は,優れたSMM特性を示し,ディスプロシウムアナログの性能に接近しています.
- ペンタフェニルボロリドリガンドによって提供される擬軸協調環境は,その高い性能に貢献する.
- この研究は,より高い温度でのアプリケーションのための,より高い軸性を持つSMMの開発を進めています.
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