アニオンテンプレッティングとメタロリガンド設計による異金属金属有機フレームワークのトポロジック制御
Sara R Halper1, Loi Do, Jay R Stork
1Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, 92093-0358, USA.
Journal of the American Chemical Society
|November 23, 2006
まとめ
研究者らは,トリス (((ディピルリナト)) リガンドと銀塩を使用して,新しい異金属金属有機フレームワーク (MOF) を合成しました. アニオン選択は,MOFトポロジーを大きく影響し,ネットワーク構造の合理的な設計を可能にします.
科学分野:
- 材料化学 材料化学について
- 超分子化学 超分子化学
- 協調化化学について
背景:
- メタル・オーガニック・フレームワーク (MOF) は,多様なアプリケーションのための調整可能な構造を提供します.
- MOF トポロジーを制御する要因を理解することは,材料設計において極めて重要です.
- ヘテロメタリックMOFは,複雑な機能の機会を提供します.
研究 の 目的:
- ヘテロメタリックMOFトポロジーにおけるコア金属イオン,コントラニオン,およびリガンド構造の影響を体系的に調査する.
- MOFネットワーク形成におけるアニオンテンプレートの役割を調査する.
- MOF合成のための合理的な設計原理を実証する.
主な方法:
- トリス (((ディピルリナト)) メタロリガンドと様々な銀 (((I)) 塩を用いた異金属MOFの合成.
- コア金属イオン (Fe3+,Co3+),コントラニオン (例えば,AgOTf,AgBF4,AgPF6,AgSbF6) とリガンド構造の体系的な変化.
- ネットワークのトポロジを決定し,単結晶から単結晶への変換を通じてアニオン交換を確認するために,X線結晶学を用いた特徴付け.
主要な成果:
- Fe3+とCo3+のコアイオンは,MOF構造に軽微な影響を及ぼし,容易な三金属Fe/Co/Agネットワークの合成を可能にしました.
- Counteranionの選択はトポロジーを大きく影響した:AgOTfとAgBF4は3D (10,3) の網を産み,AgPF6とAgSbF6は2D (6,3) の蜂巣網を産み出した.
- アニオン交換実験では,X線結晶学が単結晶から単結晶の変換を明らかにすることで,いくつかのケースで堅固なトポロジーが確認されました.
- リガンドの長さの変動はアニオンテンプレートを覆し,2D (6,3) 網のみを生成しました.
結論:
- アニオンテンプレートはMOFトポロジーを指向する重要な要因ですが,その協調能力は主要なドライバーではありません.
- リガンド構造は,アニオン効果を優先して,MOFの次元性を制御するための代替ルートを提供します.
- これらの発見は,リガンドとアニオン選択に基づくMOFアーキテクチャの合理的な設計のための基礎を提供します.
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