鉄の協調複合体におけるアニオン結合の磁気観測:スピンスイッチングケモセンサに向けて
Zhaoping Ni1, Matthew P Shores
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, USA.
Journal of the American Chemical Society
|December 17, 2008
まとめ
スピン・クロスオーバー・コンプレックスは,溶液中のアニオン結合を検出することができる. この研究では,鉄複合体がアニオン相互作用によって色とスピン状態を変化させ,磁気測定ベースのホスト-ゲストセンシングを可能にすることを示しています.
科学分野:
- 協調化化学について
- 超分子化学 超分子化学
- 材料科学 材料科学とは
背景:
- スピン・クロスオーバー (SCO) 複合体は環境刺激に敏感である.
- 溶液中のアニオン認識は,化学センサーにとって極めて重要です.
- ホスト・ゲストのやり取りのためのレスポンシブな材料の開発は,活発な研究分野です.
研究 の 目的:
- 溶液中のアニオン結合イベントの報告のためのSCO複合体の使用を実証する.
- アニオン結合強度とスピン状態のスイッチングの間の相関を調査する.
- センシングアプリケーションのためのアニオン認識とスピン状態のスイッチングの相乗効果の組み合わせを探求する.
主な方法:
- カチオンの鉄の合成と特徴付け (II) SCO複合体 (Fe) (H) (Bp) (H) (P) (P) (P) (P)) (BPh) (P) (P) (P) (P) (P)) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P)) (P) (P) (P)) (P) (P) (P) (P) (P) (P) (P)) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P)) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P) (P)
- 室温でのアニオン添加による色変化を観察するために,光譜分析 (UV-Vis).
- -40°Cでのスピン状態の移行を研究するための変数温度磁気感受性測定.
- 受容体と様々なアニオン間の水素結合相互作用の評価.
主要な成果:
- 鉄複合体は,水素結合アニオンとの相互作用で二塩基メタン溶液の微妙な色変化を示します.
- -40°Cでは,アニオン結合により,高スピン状態から低スピン状態への移行が誘発されます.
- スピン状態の変化の程度は,ホスト-ゲスト相互作用の強さと質的に相関する.
- アニオン認識とスピン状態のスイッチングの間の相乗効果が観察されました.
結論:
- スピン・クロスオーバー・コンプレックスは,溶液中のアニオン検出のための敏感な探査機として利用できます.
- 結合されたアニオン認識とスピン状態のスイッチングは,新しいセンサーメカニズムを提供します.
- マグネトメトリは,SCOの行動に基づいてホスト-ゲストの相互作用を定量化するために使用することができます.
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