スピンクロスオーバー行動を示すN-アルキル置換ビス・イミノ・ピリジン鉄イミドの合成と電子構造の決定
Amanda C Bowman1, Carsten Milsmann, Eckhard Bill
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|October 12, 2011
まとめ
新しい鉄イミド複合体は,スピンクロスオーバー行動を示し,低スピン状態と高スピン状態の間で移行します. この行動はアルキル置換物質の影響を受け,その電子構造と結合に関する洞察を提供します.
科学分野:
- 有機金属化学 有機金属化学
- 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:
- ビス・イミノ・ピリジン・リガンドは,協調化学における多用途の支架である.
- 鉄イミド複合体は,その多様な電子特性と潜在的応用により興味を惹きます.
研究 の 目的:
- 新規のN-アルキル置換ビス・イミノ・ピリジン鉄イミド複合体を合成し,特徴づけること.
- これらの新しい化合物のスピンクロスオーバー行動と電子構造を調査するために.
主な方法:
- 鉄イミド複合体の合成 鉄二酸化窒素前駆体へのアジド添加による.
- SQUID磁気測定,X線 difraktion,およびMössbauerスペクトロスコーピーを用いた特徴付け.
- 電子構造分析のための計算研究とX線吸収スペクトロスコピー.
主要な成果:
- 3つの新しいN-アルキル置換のビス・イミノ・ピリジン鉄イミド複合体が成功して合成されました.
- スピン・クロスオーバーの行動は,アイソメリック鉄イミドで観察され,一つはより完全な移行を示しました.
- X線屈折により,短いFe-N (イミド) 結合を持つ平面構造が明らかになり,リガンドの2電子減少を示した.
- モッズバウアー光譜法により,二磁性基底状態が確認され,スピンクロスオーバーがサポートされ,S=0からS=1への移行の熱力学パラメータが得られました.
結論:
- 合成された複合体は調節可能なスピンクロスオーバー特性を示す.
- 電子構造は,S=0状態のイミジル基と結合した低スピンのフェリック中心として最もよく説明されます.
- 鉄を中心としたスピンの移行が,中間のスピンのフェリックイオンに,より高い温度でS=1状態を説明します.
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