スピン・クロスオーバー 擬四面体ビス・フォーマーザネート鉄複合体
Raquel Travieso-Puente1, J O P Broekman1, Mu-Chieh Chang1
1Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|April 15, 2016
まとめ
この研究は,希少な四座標鉄 (II) 複合体におけるスピン・クロスオーバーを詳細に説明する. 化合物は,リガンド特性と電子構造によって影響を受け,低スピン (S=0) と高スピン (S=2) の状態を切り替える.
科学分野:
- 無機化学
- 材料科学
- 量子化学について
背景:
- スピン・クロスオーバー (SCO) 現象は分子スイッチとメモリデバイスにとって極めて重要です.
- 4座標複合体は,リガンドフィールドの安定エネルギーにより,SCOをめったに表さない.
- ビス・フォーマーザネート・リガンドは,移行金属複合体に対してユニークな電子特性を有する.
研究 の 目的:
- 擬似四面体ビス (((フォームザナート) 鉄 (((II)) 複合体を合成し,特徴づけること.
- この稀な四座標系における スピン・クロスオーバーの 行動を調査するためです
- スピン状態の移行と電子特性を支配する要因を解明する.
主な方法:
- 構造分析のための単一結晶X線微分
- スピンの状態を決定する磁気感受性の測定.
- 電子的および振動的特徴化のためのUV-VisおよびIRスペクトロスコーピー.
- 電子構造計算のための密度関数理論 (DFT).
主要な成果:
- 鉄 (II) 複合体は,低スピン (S=0) と高スピン (S=2) の間の熱スピンクロスオーバーを示す.
- 構造的変化は,高スピン状態への移行時にFe-Nボンドの長さを増加させ,N-Nボンドを収縮させる.
- 1電子の還元により,低スピン (S=1/2) のアニオンとなる.
- DFT計算は,観察されたスピンクロスオーバーと電子特性を合理化します.
結論:
- 擬四面体協調幾何学は,鉄 (II) 複合体におけるスピン・クロスオーバーをサポートする.
- ビス ((formazanate) リガンドの π 受容体の性質は,低スピン状態を安定させる.
- 電子構造とリガンドの設計は,協調化合物のスピンクロスオーバー行動を制御する鍵です.
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