構造的秩序と液体の水の異常との関係
J R Errington1, P G Debenedetti
1Department of Chemical Engineering, Princeton University, New Jersey 08544-5263, USA.
Nature
|February 24, 2001
まとめ
水のような液体の構造的順序を定量化することは難しい. この研究は,圧縮によって秩序が低下し,異常な性質を説明するユニークな液体水領域を明らかにしています.
科学分野:
- 物理化学 物理化学
- マテリアルサイエンス 材料科学
- 計算物理学の物理
背景:
- 結晶固体は,液体やガラスとは異なり,よく定義された構造を持っています.
- 液体,特に水素結合の水における構造的順序を定量化することは困難である.
- 水の異常な運動および熱力学的性質は,その構造と関連しています.
研究 の 目的:
- 水中の構造と性質の関係を定量的に理解する.
- 水のモデルにおける変換的および指向的順序を調査する.
- 水の異常な性質の構造的根拠を特定するために.
主な方法:
- 水のモデルの分子動力学シミュレーション.
- トランスレーションおよびオリエンテーション順序のパラメータの分析.
- 構造的に異常な地域の特定.
主要な成果:
- 水中の構造的に異常な領域が特定され,密度依存の極度の順序で囲まれています.
- この領域内の圧縮で秩序は低下し,それに結合した翻訳的および方向的秩序がある.
- この地域には,異常な拡散性と熱膨張の条件が含まれています.
結論:
- 水中の構造的異常は定量化され,運動および熱力学的性質と関連しています.
- 構造的秩序が増加するにつれて,一連の異常が連続的に発生します.
- この研究は,水のユニークな行動を理解するための定量的な枠組みを提供します.
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