ビピリミドール基根ブリッジドディランタニド複合体における交換結合と磁気阻害
Selvan Demir1, Joseph M Zadrozny, Michael Nippe
1Department of Chemistry, University of California, Berkeley, 94720, United States.
Journal of the American Chemical Society
|November 1, 2012
まとめ
研究者らは,新しいビピリミジル基幹ブリッジドディランタニド複合体を合成した. これらの複合体は,強力な磁気結合と単分子磁石の振る舞いを表しており,分子磁気における潜在的な応用がある.
科学分野:
- 協調化化学について
- マテリアルサイエンス 材料科学
- マグネチズム (磁気) とは
背景:
- ランタニド複合体は,そのユニークな磁気性により興味を惹きます.
- ラジカル・ブリッジ・コンプレックスは,強い磁気交換相互作用の経路を提供する.
- 単分子磁石 (SMM) は,高密度データストレージと量子コンピューティングの開発に不可欠です.
研究 の 目的:
- 新規のビピリミジル基幹ブリッジドディランタニド複合体を合成し,特徴づけること.
- ランタニドイオンとビピリミジル基間の磁気交換結合を調査する.
- 単一分子磁石としてのこれらの複合体の潜在能力を探求する.
主な方法:
- 3つの新しいディランタニド複合体の合成: [ ((Cp* ((2) Ln) ((2) (((μ-bpym (((•)))))) ((+)) (Ln = Gd, Tb, Dy).
- 磁気相互作用と行動を探査するために,磁気感受性測定 (dc) を行う.
- 磁気データを分析して,結合定数とリラックスダイナミクスを決定する.
主要な成果:
- 強いランタニド ((III) -ビピリミジル基 (Ln ((III) -bpym (((•-)) 交換結合は,合成されたすべての複合体で観察されました.
- ガドリニウム (III) 複合体は,S = 13/2 基底状態で反鉄磁気結合 (J = -10 cm (-1)) を示した.
- テルビウム (III) 複合体とディスプロシウム (III) 複合体は,単一分子磁石の振る舞いを示し,有意なリラックスバリア (U (eff) =44 (eff) =44 (eff) 2) と87.8 (eff) =87.8 (eff) 3) センチメートル (cm) -1),それぞれを示した.
- ディスプロシウム (III) 複合体は,6.5Kでのフィールド冷却/ゼロフィールド冷却の微分と磁気ヒステリシスを示し,これは緩やかな磁気放松を示す.
結論:
- ビピリミジル基は,ディランタニド系における強い磁気交換を媒介する効果的な橋渡しリガンドとして機能する.
- 合成されたTb (III) とDy (III) コンプレックスは,大きな磁気アニソトロピーにより有望な単分子磁石特性を示しています.
- これらの発見は,ナノテクノロジーにおける潜在的な応用を持つ新しい分子磁気材料の設計に寄与します.
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