水は,水害性の表面で:弱い水素結合と強い方向効果がある
L F Scatena1, M G Brown, G L Richmond
1Department of Chemistry, University of Oregon, Eugene OR 97403, USA.
Science (New York, N.Y.)
|May 8, 2001
まとめ
疎水界面の水分子は,一般的な仮定に反して,弱い水素結合を示す. 彼らの方向性は,有機相との相互作用によって大きく影響され,これらの表面の近くの水の行動に影響を与えます.
科学分野:
- 物理化学 物理化学
- 表面科学とは,地表科学である.
- インターフェイス現象
背景:
- 防水界面における水の振る舞いを理解することは,様々な科学分野において極めて重要です.
- 既存のモデルでは,水と水害性の表面との間に強い水素結合が提案されていることが多い.
研究 の 目的:
- 炭素四塩化物/水,炭化水素/水界面における水の分子構造と水素結合を調査する.
- 水と水害環境の相互作用に関する支配的な理論に異議を唱え,またはそれを確認する.
主な方法:
- 振動光譜を用いて,指定されたインターフェイスで分子構造を選択的に探査した.
- 分析されたスペクトルデータを用いて,水素結合の強さと分子指向を推論した.
主要な成果:
- これらのインターフェイスで,隣接する水分子の間で,有意に弱い水素結合が観察されました.
- 有機相との相互作用により,水分子の実質的な指向が示されている.
- この発見は,水害を嫌う界面での強い水素結合という広く受け入れられている概念と相反する.
結論:
- 水嫌性のインターフェイスにおける水の水素結合は,これまで考えられていたよりも弱い.
- インターフェイスの水分子は,隣接する有機相との相互作用によって強く指向されています.
- これらの発見は,水害性の表面に隣接する水とその浸透を記述するモデルの見直しを必要としています.
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