イオンを含む水中ナノドロップの結晶性の遅延
Richard J Cooper1, Matthew J DiTucci1, Terrence M Chang1
1Department of Chemistry, University of California , Berkeley, California 94720-1460, United States.
Journal of the American Chemical Society
|December 30, 2015
まとめ
単一のLa(3+) イオンは,中性クラスターよりも多くの水分 (n ≥ 375) を要求することによって,ナノドロップの水結晶化を遅らせます. このイオンは水素結合ネットワークを 1 nm 離れたところまで破壊する.
科学分野:
- 物理化学
- ナノスケール科学
- スペクトロスコーピー
背景:
- 水は狭いナノスケール環境で ユニークな特性を発揮します
- 表面効果は低温で水塊結晶化に影響する.
- イオンは水分子の振る舞いを大きく変えます
研究 の 目的:
- 水のナノドロップの結晶化に作用する単一の三価イオンであるLa3+を調査する.
- イオンを含む水の大きさに依存する結晶化行動を決定する.
- 水中の水素結合ネットワークを イオンがどう破壊するかを理解するためです
主な方法:
- サイズで選択されたLa3+H2O) n群の赤外線光分解スペクトロスコーピー.
- 550個の水分を含んだナノドロップの実験調査
- 実験結果を裏付ける分子動力学シミュレーション
主要な成果:
- ナノドロップを含むLa(3+) の結晶化は,n ≥375の水分で発生する.
- これは中性水群で観測された量より約100個多い.
- La(3+) は水素結合ネットワークを第三の溶解層 (~1 nm) 以外で破壊する.
結論:
- 単一の三価イオンはナノドロップの水結晶を大きく変化させる.
- 水素結合ネットワークに対するイオンの影響は,直接の溶解殻をはるかに超えています.
- この研究は,閉じ込められた水に対するイオンの長距離構造的影響を明らかにしています.
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