ヘプタシアノモリブデート基の単分子磁石で,シアン化物化合物のエネルギーバリアが最も高い
Kun Qian1, Xing-Cai Huang, Chun Zhou
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.
Journal of the American Chemical Society
|August 24, 2013
まとめ
研究者らは,ヘプタシアノモリブデートを使用した最初の単一分子磁石 (SMM) を含む,新しいマンガン・モリブデン (Mn2Mo) 分子を開発した. これらの分子は,シアン化物ベースのSMMの記録的な性質を示しています.
科学分野:
- 分子磁気は分子磁気である.
- 協調化化学について
- マテリアルサイエンス 材料科学
背景:
- シングル分子磁石 (SMM) は,ゆっくりとした磁気緩和を示す分子材料です.
- シアン化物ベースのSMMは,リガンド設計を通じて調節可能な磁気特性を提供します.
- 軌道上の変性アニオンは,新しいSMM開発の機会を提供します.
研究 の 目的:
- 新型三核分子Mn2Moを合成し,特徴づけること.
- これらの新しい分子システムの磁気特性を調査するために.
- SMMにおけるヘプタシアノモリブダートアニオンの可能性を調査する.
主な方法:
- 3つの三核のMn2Mo複合体の合成.
- 構造的決定のための単結晶X線 difraktion.
- 磁気感受性および直流 (dc) の磁気化測定.
主要な成果:
- 3つのMn2Mo分子が[Mo(CN) 7](4-) アニオンを備えた製剤が成功しました.
- ヘプタシアノモリブデートに基づく最初のSMMの発見.
- シアン化物ベースのSMMの記録ブロック温度とエネルギーバリア (U = 40.5cm(-1)) を記録します.
- 単一結晶における広範囲のヒステレスループと量子トンネリングのステップの観測.
結論:
- [Mo(CN) [7](4-) アニオンは,高性能SMMの実現可能な構成要素である.
- これらの発見は,分子磁気,特にシアン化物ベースのシステムの分野を前進させる.
- 観測された性質は,先端の磁気材料の将来の設計のための道を開く.
関連する概念動画
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CFT focuses on...
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02:34Structural Isomerism
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Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...