MoS43--ブリッジド・ディランタニド・コンプレックスにおける強い鉄磁気交換結合と単分子磁気
Lucy E Darago1, Monica D Boshart2, Brian D Nguyen2
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|May 24, 2021
まとめ
この研究では,ランタニドとモリブデン間の強い鉄磁気交換を示す新しい4d-4f化合物を合成した. これらの材料は,高度な単分子磁石や散発磁石材料の開発の可能性を示しています.
科学分野:
- 無機化学
- 材料科学
- マグネト化学
背景:
- 新しい4d−4fヘテロメタリック化合物の調査は,分子磁性の進歩に不可欠です.
- 多核複合体の金属交換相互作用を理解すると,磁気材料の設計に役立つ.
研究 の 目的:
- 新しい三核4d-4f化合物を合成し,特徴づけること.
- 電子構造と磁気特性を研究し,金属対金属の電荷移転と磁気交換に焦点を当てた.
- 単一分子の磁石として これらの化合物の可能性を探る
主な方法:
- 三核4d-4f化合物の合成 [Co(C5Me5) 2) [(C5Me5) 2Ln ((μ-S) 2Mo ((μ-S) 2Ln ((C5Me5) 2),1-Ln (Ln = Y,Gd,Tb,Dy) について
- UV-Vis-NIR拡散反射スペクトロスコーピー,DFT計算,電子パラマグネティック共振 (EPR) および磁気感受性測定を用いた特徴付け.
- 遅い磁気リラックス研究のためのAC磁気感受性の分析.
主要な成果:
- 化合物は,硫黄による低エネルギー金属対金属の電荷移転をMo{\displaystyle \mathrm {Mo} }4d) からL{\displaystyle \mathrm {L} }5d) 軌道に表している.
- 有意な電子移転と強い鉄磁気Ln- Mo交換相互作用が観察されました.
- 化合物1-Gdは,大きなGd-Mo交換定数 (J = +16.1(2) cm−1を持つS = 15/2の基底状態を示している.
- 化合物1-Tbと1-Dyは緩やかな磁気リラックスを示し,1-Dyは4d金属を含む複合物にとって報告された最大の熱リラックスバリア (Ueff = 68 cm−1) を表している.
結論:
- この研究は,n−4f磁気交換の強化のための一般化可能な経路を示している.
- これらの発見は,新しいnd-4f単分子磁石と,特異な特性を有する散発磁石材料を設計するための道を開きます.
- 観測された強い磁気交換と緩やかな放緩は,これらの化合物の分子磁気における可能性を強調しています.
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