単一の金属中心を持つ単一分子磁石の振る舞いは,周辺リガンドの改変によって強化されています
Titel Jurca1, Ahmed Farghal, Po-Heng Lin
1Centre for Catalysis Research and Innovation and Department of Chemistry, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada.
Journal of the American Chemical Society
|September 9, 2011
まとめ
ビス・イミノ・ピリジンのピンチャーリガンドを備えた2つの新しいコバルト (II) 複合体は,ユニークな幾何学とスピン軌道結合により,単分子磁石 (SMM) 行動を示し,ゆっくりとした磁気化の緩和を可能にします.
科学分野:
- 無機化学 無機化学とは
- マテリアルサイエンス 材料科学
- 量子マグネティズム 量子マグネティズムとは
背景:
- 単分子磁石 (Single-Molecule Magnets,SMMs) は,ゆっくりとした磁気緩和を示す分子システムである.
- コバルト (II) 複合体は,その電子特性により,SMMの有望な候補である.
- ピンサー・リガンドは,金属イオンに対して堅固な調整環境を提供する.
研究 の 目的:
- 新しい単核コバルト ((II)) 複合体を合成し,特徴づけること.
- これらの複合体の磁気特性を調査するために.
- 単分子磁石 (SMM) の行動の可能性を探求する.
主な方法:
- ビスミノピリジンとイソチオシアネートリガンドを用いた2つの単核コバルト (II) 複合体の合成.
- 分子構造と協調幾何学を決定するX線結晶学.
- リラクゼーションダイナミクスを研究するための磁気感受性測定.
主要な成果:
- 2つの異なる単核C02 (II) 複合体の製造に成功した.
- 両複合体は,基底平面から移動したCo ((II) センターを持つ歪んだ正方形ピラミッド形幾何学を採用しています.
- d(7) Co(II) イオンにおける重要なスピン軌道結合の証拠.
- SMMの行動の特徴である磁気化の緩やかな緩和が観察されました.
結論:
- 合成されたコバルト (II) 複合体は,単分子磁石 (SMM) の性質を示しています.
- 歪んだ正方形ピラミッド形の幾何学は,ゆっくりとした磁気放松を誘導するために不可欠です.
- これらの発見は,分子磁気材料の開発に寄与する.
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