ビス・ディオクソレン・ブリッジ・ダイヌクレア・コバルト・コンプレックスにおける1段階または2段階のバレンスのタウトメア変換の起源を理解する
Gemma K Gransbury1, Brooke N Livesay2, Jett T Janetzki1
1School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia.
Journal of the American Chemical Society
|May 16, 2020
まとめ
この研究では,コバルト複合体におけるバレンスのタウトメリズム (VT) を調査し,高度な材料での潜在的な使用のための電子転送の制御を示しています. 異なる電子構造とVT行動が観察され,次世代のVT複合体への道を開きました.
科学分野:
- 協調化学
- 材料科学
- 超分子化学
背景:
- バレンスのタウトメリズム (VT) は,リバーシブルな分子内電子移転であり,リドックス活性リガンドと金属の間に発生する.
- 双核コバルト複合体とビス・ダイオキソレン・ブリッジは,調節可能な2段階のVT経路を提供する.
- これらの複合体は,分子装置および材料における応用のために,スピンクロスオーバー複合体よりも優れている.
研究 の 目的:
- 新型二核コバルト複合体をスピロビー・インダン (spirobi) またはテトラブロモ・スピロビー・インダン (tetrabromo-spirobi) ブリッジリングリガンドで合成し,特徴づけること.
- 結合体設計と補助結合体が,バレンスの整合性行為に及ぼす影響を調査する.
- VT トランジションを制御する熱力学パラメータと電子通信を明らかにする.
主な方法:
- spiroH4またはBr4のブリッジリングリガンドとMentpa補助リガンドを含む4つの二核コバルト複合体の合成.
- 構造的,磁気的,スペクトル学的技術を用いた特徴付け.
- 密度関数理論 (DFT) 計算と電気化学の研究,混合バレンスの{ZnII-cat-SQ-ZnII}アナログを含む.
主要な成果:
- 一段階の部分VT,二段階のVT,不完全なVT,温度不変状態を含む多様なVT行動が観察されました.
- 電気化学,DFT,およびZnIIアナログを用いた1段階および2段階VTの解明された熱力学パラメータ.
- リガンドとリドックスポテンシャルのマッチングに基づく合理化されたVTトランジションプロファイル.
結論:
- この研究は,高度な2段階のVT複合体の明確な設計戦略を確立しています.
- 弱い分子内結合を持つ混合バレンスのクラスIIおよびII-IIIビス ((ダイオキソレン) リガンドを組み込むことが鍵です.
- この研究は,電子特性を特化した次世代のVT材料の発展の道を開きます.
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