第一原理分子力学 ナノスリットの2D水の自発的な凍結移行のシミュレーション
Jian Jiang1, Yurui Gao2, Weiduo Zhu1
1Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States.
Journal of the American Chemical Society
|May 19, 2021
まとめ
最初の原理のシミュレーションでは,ナノスリットの二次元 (2D) の水の自発的な凍結が示され,新しい氷の構造が形成されます. この2次元結晶の氷は 既存のルールに異議を唱え 水についての理解を広げています
科学分野:
- 凝縮物質物理学
- 材料科学
- 物理化学
背景:
- 二次元 (2D) の氷は,水氷の塊と似ており,様々な結晶構造を持っています.
- 2Dの氷の構造に関する以前の予測は,古典的な分子動力学 (MD) のシミュレーションに大きく依存していた.
研究 の 目的:
- 2次元液体の水の自発的な凍結移行を水害性ナノスリットに閉じ込めています.
- 第1原理のMDシミュレーションを使用して,異なる圧力および温度条件下での様々な2D氷の構造の形成を調査する.
主な方法:
- 第1原理の分子動力学 (MD) シミュレーションを用いて,水害性ナノスリットの水の振る舞いを研究する.
- 2D水の自発的な凍結と構造的移行を観察するために,側面の圧力と温度を変化させる.
主要な成果:
- ナノスリットの2D液体の自発的な凍結が観察され,様々な結晶構造が形成された.
- 2.5GPaと250Kで6.0 Å幅のナノスリートにジグザグ状の水鎖を持つ単層氷を特定した.
- 4.0 GPa と 300 K の 8.0 Å 幅のナノスリットで,大量氷 VII に似ている新しい二層氷を発見した.
結論:
- 最初の原理のシミュレーションは,古典的なシミュレーションでは簡単に探求できないユニークな相空間にアクセスできます.
- 観測された2D結晶の氷は,従来の氷のルールに従わない.
- この研究は,ナノスケールで閉じ込められた新しい氷のポリモルフの可能性を強調しています.
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