二核コバルト複合体で,前例のないアノド・カトド・レドックス・スイッチを搭載し,単一分子磁気活動のための単一分子磁気活性スイッチを搭載しています
Skye Fortier1, Jennifer J Le Roy, Chun-Hsing Chen
1Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|September 3, 2013
まとめ
この研究では,単一分子磁石の振る舞いを示すコバルト複合体を導入しました. 酸化および還元された形態では,反転可能な磁気スイッチングを示し,二重のオン/オフ制御を提供します.
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
- マグネト化学 マグネト化学
背景:
- パラ磁性二核コバルト (II) 複合体は,磁性応用において興味をそそります.
- 単分子磁石 (SMM) は,その機能のために特定の構造および電子特性を要求します.
研究 の 目的:
- 新型二核コバルト ((II)) 複合体の酸化還元反応と磁気特性を調査する.
- 単分子磁石の切り替え可能な単分子磁石としてのこの複合体の可能性を調査する.
主な方法:
- 二核コバルト ((II) 複合体 dmp2Nin{Co[N(SiMe3) 2}の合成と特徴づけ
- 化学的および電気化学的方法を用いた1電子酸化および還元.
- 構造分析 (X線 difraktion) と磁気感受性の測定. 構造分析 (X線 difraktion) と磁気感受性の測定. 構造分析 (X線 difraktion) と磁気感受性の測定. 構造分析 (X線 difraktion) と磁気感受性の測定.
- 電子パラマグネティック共振 (EPR) スペクトロスコーピー.
主要な成果:
- 複合体の反転可能な1電子酸化と還元が達成され,根性塩 [1(OEt2) ](+) と [1](-) が形成されました.
- レドックス活性がニンディゴリンガンドに局限され,リンガンドを中心としたラジカルが生成されました.
- これらのラジカルはコバルト (II) センターの間の磁気結合を媒介し,SMMの行動を誘導します.
- 酸化された形と還元された形の両方がSMMの性質を示します.
結論:
- 二核コバルト複合体は,リダックス操作で,リガンド中心の基質形成を示しています.
- このシステムは,反転可能な二重"ON/OFF"スイッチング機能を持つ単一分子磁石の最初の例を示しています.
- この発見は,切り替え可能な分子磁性材料の設計の道を開く.
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