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Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
相対的および非相対的水素結合. クリスタル工学の演習です
T L Nguyen1, F W Fowler, J W Lauher
1Department of Chemistry, State University of New York, Stony Brook, NY 11794, USA.
Journal of the American Chemical Society
|November 1, 2001
まとめ
尿素とオキサミドは,通常,異なる水素結合ネットワークを形成します. 同結晶化により,これらの分子が新しい2Dベータネットワークまたは異常な形状を形成し,それらの典型的な構造を変更することが明らかになった.
科学分野:
- クリスタル・エンジニアリング (Crystal Engineering) とは
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
背景:
- 尿素と酸化物は通常,水素結合によって1Dアルファネットワークを形成する.
- これらのネットワークには特徴的な繰り返しの距離があり,尿素の場合は約4.60 Å,オキサミドの場合は約5.05 Åである.
研究 の 目的:
- ビピリジン誘導体によるグリシン尿素とグリシンオクサミドの共結晶化行動を研究する.
- 不均衡なネットワーク距離の分子が同じ結晶の中で共存することを余儀なくされたときの構造的結果を決定する.
主な方法:
- ビピリジン化合物による尿素およびオキサミド誘導体の共結晶化.
- 結果の8つのコクリスタルをX線 difraktion 分析した.
主要な成果:
- 全尿素および全酸化素共結晶は,特徴的なアルファネットワークを維持した.
- 3つの混合コクリスタルは,2Dベータネットワークを形成し,尿素とオキサミドのサブネットワークを交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互に交互を交互に交互に交互に交互に交互に交互を交互に交互に交互を交互に交互に交互を交互に交互に交互に交互を交互に交互に交互を交互に交互を交互に交互を交互に交互を交互に交互を交互を交互に交互を交互に交互を交互を交互を交互に交互を交互を交わ
- 1つの混合結晶は正常な尿素αネットワークを示し,オクサミドは分子内水素結合の形状を採用した.
結論:
- 同結晶化は,平均的な繰り返しの距離を持つ新しい2Dベータネットワークの形成につながる可能性があります.
- いくつかの場合,競合するネットワーク形成は,分子内相互作用を最大化するために異常な分子構成を誘導することができます.
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