柔軟なオープンフレームワークにおける異例のイオン交換選択性ランタン (((III) テトラキスフォスフォネート
Monika Plabst1, Lynne B McCusker, Thomas Bein
1Department of Chemistry and Biochemistry and Center for NanoScience (CeNS), University of Munich (LMU), Butenandtstrausse 11, 81377 Munich, Germany.
Journal of the American Chemical Society
|November 20, 2009
まとめ
この研究は,フレームワークの柔軟性により,柔軟な材料NaLa ((H ((4) L) が選択的に単価カリオンを交換することを示しています. そのチャネルは脱水時に収縮し,ゲストイオンサイズと水分エンタルピーに適応します.
科学分野:
- マテリアルサイエンス 材料科学
- 無機化学 無機化学とは
- クリスタログラフィーです.
背景:
- アニオン型オープンフレームワークの材料は,イオン交換のための調整可能な性質を提供します.
- NaLa (NaLa (PO) 3H) 2CH-C6H4CH4PO3H) 2H4H2O (NaLa (H4) L) は,選択的なイオン結合の可能性のある,最近発見された物質です.
研究 の 目的:
- イオン交換行動とNaLa (H) のフレームワークの柔軟性との関係を明らかにする.
- NaLa (H) の電荷選択性を調査するために,様々な金属カチオンに対して.
主な方法:
- 異なる金属カチオンによるイオン交換実験.
- EDXとICP-OESを用いたエレメンタル分析.
- 構造的および水分化研究のためのX線 difraktionおよび熱重力測定分析.
- 結晶構造を決定するためのリートヴェルド精錬.
主要な成果:
- NaLa (H) は単価イオンに対して例外的な選択性を示し,高価イオンを拒絶する.
- フレームワークの柔軟性は,可逆的な水分補給/脱水によって確認され,細胞の体積が15%減少した.
- リートヴェルドの精製により,Na+の調整変化を含むカチオン特異のチャネル縮小メカニズムが明らかになった.
結論:
- NaLa ((H ((4) L) のチャージ選択性は,ゲストキャッションとフレームワークの適応のサイト固有の役割に起因する.
- フレームワークの柔軟性により,NaLa(H(4) L) は,単価ゲストカチオンのイオン半径と水素化エンタルピーに特異的に適応することができます.
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