[Mn(III) 4Ln(III) 4) カリックス[4]アレンのクラスターは,強化された磁気冷却器と分子磁石として使用されます
Georgios Karotsis1, Stuart Kennedy, Simon J Teat
1School of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, Scotland, UK.
Journal of the American Chemical Society
|August 4, 2010
まとめ
新しいマンガン・ランタニド・クラスターは,磁気冷媒や分子磁石として有望を示しています. これらのカリキサレンベースの化合物は,高度な低温アプリケーションのために調整可能な磁気特性を示す.
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:
- メチレン・ブリッジド・カリックス[4]アレンは,協調化学における多用途リガンドである.
- 3d/4f金属クラスターは,移行金属とランタノイドの組み合わせにより,ユニークな磁気特性を提供します.
研究 の 目的:
- メチレン・ブリッジドキャリックス[4]アーネスを用いて新しい3d/4f金属クラスターを合成し,特徴づけます.
- これらのクラスターの磁気特性および磁気冷媒および分子磁石としての潜在的な応用を調査する.
主な方法:
- カリキサレンベースのMn(III) / Ln(III) クラスターの合成.
- 構造分析のための単結晶X線 difraktion. 構造分析のための単結晶X線 difraktion.
- 磁気感受性および磁化測定. 磁気感受性および磁化測定. 磁気感受性および磁化測定. 磁気感受性および磁化測定.
主要な成果:
- [Mn(III) 4Ln(III) 4]クラスター (Ln = Gd,Tb,Dy) の家族を合成し,正方形の内にある正方形の構造をした.
- クラスター1 (Ln=Gd) は,スピン状態と磁性同otropyの高密度を示し,磁気冷却に適しています.
- クラスター2およびクラスター3 (Ln=Tb, Dy) は,分子磁石の振る舞いを示す,ゆっくりとした磁気化の緩和を示しています.
結論:
- メチレンブリッジされたカリックス[4]アレンの組み込みにより,調整可能な磁気機能を持つ複雑な3d/4fクラスターの構築が可能になります.
- これらの化合物は,低温の磁気冷却と分子磁気学のアプリケーションのための有望な候補者を表しています.
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