高圧を利用して,多孔性,多形性,および非多孔性分子構造 Zn(CN) 2 の格子膨張を生成する
Saul H Lapidus1, Gregory J Halder, Peter J Chupas
1X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Journal of the American Chemical Society
|May 3, 2013
まとめ
高圧では,亜鉛シアン化物 (Zn(CN) 2) を新しい結晶と無形相に変換します. 流体による影響を受けたこの圧力による構造変化は,潜在的な応用を持つ新種の多孔性物質を作り出すことができます.
科学分野:
- 材料科学 材料科学とは
- 高圧物理 高圧物理
- クリスタログラフィーです.
背景:
- 亜鉛シアン化物 (Zn(CN) 2) のような分子フレームワーク材料は,外部刺激下で複雑な構造的行動を示します.
- 圧力による相変化の理解は,特異な性質を持つ新しい材料の設計に不可欠です.
研究 の 目的:
- 分子フレームワーク材料Zn (((CN)) 2.の高圧振る舞いを体系的に調査する.
- 新しい圧力誘発相の構造を解明し,その形成を左右する要因を理解する.
- 圧力を用いて新しい多孔性物質を生成する可能性を調査する.
主な方法:
- シンクロトロン粉末 difraktion を用いた高圧実験.
- Ab initio構造の決定は,チャージ・フリッピングとダイレクト・スペース・メソッドを用いて行われます.
- 圧力を伝達する液体の体系的な変異は,移行経路を検知するために.
主要な成果:
- Zn(CN) 2の5つの新しい相の発見: 4つの結晶と1つの無形.
- 圧力および流体に依存する移行の識別,多孔ポリモルフ (ダイアモンド型,ロンダライト型,ピライト型) への再構成変換を含む.
- 多孔構造の形成に関連した大幅な体積膨張 (最大2倍) の観察.
結論:
- 圧力を伝達する液体は,Zn (((CN) 2.2) の高圧相変遷を決定的に影響する.
- 水位圧は,相互に浸透したフレームワークシステムから新しい多孔質な材料を作成するために利用できます.
- 周囲の圧力下では新しい多孔性相 (dia-Zn(CN) 2,lon-Zn(CN) 2) を保持する能力は,それらの潜在的有用性を強調しています.
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