アンフィフィリックな有機結晶
J J Segura1, A Verdaguer, M Cobián
1Centre d'Investigació en Nanociència i Nanotecnologia, CIN2 (CSIC-ICN), Edifici CM7, Esfera UAB, Campus de Bellaterra, E-08193 Barcelona, Spain.
Journal of the American Chemical Society
|November 18, 2009
まとめ
アンフィフィリックな性質,つまり水を引き寄せ,反撃する能力は,L-アラニンなどの結晶固体で実証されています. この発見は,有機分子を超えて分子結晶の概念を拡張し,二極の起源を明らかにします.
科学分野:
- マテリアルサイエンス 材料科学
- 表面科学とは,地表科学である.
- クリスタログラフィーです.
背景:
- アンフィフィリシティ,すなわち双重の水性および水害性の性質は,通常,フォスフォリピドや表面活性物質などの有機分子と関連しています.
- この特性は,ジャヌス粒子やパターンの表面を含む人工構造に拡張されています.
研究 の 目的:
- 結晶固体のアンフィフィリックな性質を証明し説明する.
- 水蒸気にさらされたときのl-アラニン結晶の振る舞いを調査するために.
- 分子結晶におけるアンフィフィリシティの根本的なメカニズムを解明する.
主な方法:
- 原子力顕微鏡 (AFM) による,l-アラニンの異なる割れ面での測定.
- 分子相互作用と表面の振る舞いを分析するためのコンピュータシミュレーション.
- 水蒸気に結晶表面を晒し,対照的な反応を観察する.
主要な成果:
- L-アラニン結晶は,様々な表面で水を引き寄せ,反発させ,アンフィフィリックな行動を示します.
- 原子力顕微鏡では,水蒸気との明確な表面相互作用が明らかになりました.
- コンピューター・シミュレーションにより,このアンフィフィリティの起源として分子の二極性の性質が特定されました.
結論:
- アンフィフィリティは有機分子に限定されず,結晶固体にも見られます.
- 分子結晶内の二極相互作用は,それらの両極性特性を支配する.
- この発見は,他の二極分子結晶にも一般化できます.
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