[{CH3) 4N}[{C5H5NH}]0.8{{CH3) 3NH}0.2]U2Si9O23F4 (USH-8):有機的にテンプレートされたオープンフレームウランシリケート
Xiqu Wang1, Jin Huang, Allan J Jacobson
1Department of Chemistry, University of Houston, Houston, Texas 77204-5003, USA.
Journal of the American Chemical Society
|December 19, 2002
まとめ
新しいウラン・フッ素シリケート・フレームワークUSH-8は,水熱で合成されました. この材料は,独特のシリケート二重層と有機カチオンが占有するチャネルを特徴とし,新しい材料の応用の可能性を提供します.
科学分野:
- 無機化学 無機化学とは
- 材料科学 材料科学とは
- クリスタル・エンジニアリング (Crystal Engineering) とは
背景:
- オープンフレームワークの材料は,様々な用途に合わせて調整可能な特性を提供します.
- ウラン基化合物は,そのユニークな電子的および構造的特性により興味を惹きます.
- フロロロシリケートは,多様な構造モチーフを持つ無機化合物のクラスを表しています.
研究 の 目的:
- 新しいオープンフレームワークのウランフローロシリケートを合成し,特徴づけること.
- フレームワーク内の構造的特徴とカテーション順序を調査する.
- イオン交換や触媒などの分野で,そのような材料の潜在能力を探求する.
主な方法:
- テトラメチラモニウム水酸化物とピリジンHFを用いた水熱合成.
- 構造的決定のための単結晶X線 difraktion.
- フレームワークの構成とチャネル構造の分析.
主要な成果:
- ウランフローロシリケートの合成が成功しました [(CH3) 4N][(C5H5NH) 0.8(((CH3) 3NH) 0.2]U2Si9O23F4 (USH-8).
- フレームワークは,UO3F4の五角形の2ピラミッドで結ばれたシリケート二重層で構成されています.
- 構造は[010]に沿って12環のチャネルと[100]に沿って7環のチャネルを示している.
- オーダーされたテトラメチルアモニウム (TMA) カチオンは狭いチャネルサイドを占有し,無秩序なピリジニウムとトリメチルアモニウムカチオンはより広いチャネルセクションを占有する.
結論:
- 新型USH-8化合物は,ゲスト分子相互作用の可能性のある複雑なオープンフレームワーク構造を示しています.
- 経路内の有機カチオンの秩序と無秩序の分布は,構造を指揮する役割を強調する.
- この合成は,ウランベースのオープンフレームワーク素材のライブラリを拡張します.
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