Ru ((0001) と Pt ((111) の最初の氷層の成長と構造
Sabine Maier1,2, Barbara A J Lechner1, Gabor A Somorjai1,3
1Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|February 5, 2016
まとめ
金属の表面の水を調べると,最初の水層は
科学分野:
- 表面科学
- 凝縮物質物理学
- 物理化学
背景:
- 金属の表面での水吸収は,様々な現象を理解するために不可欠です.
- 最初の水層は 氷の形成の構造を決定します
- Ru(0001) と Pt(111) は,表面相互作用を研究するためのモデルシステムです.
研究 の 目的:
- Ru ((0001) と Pt ((111) の初期水層の分子レベルの構造と成長を解明する.
- 無形から結晶の構造への移行を調査する.
- 氷の形成に影響を与える構造的欠陥を特定する.
主な方法:
- 分子レベルの解像度を達成するためにスキャニング・トンネル顕微鏡 (STM) が使用された.
- 実験はRu (0001) とPt (111) の金属表面で行われた.
- 異なる氷の相を観測するために,異なる温度が使用されました.
主要な成果:
- 最初の水層は六角形の構造を形成し,基底と秩序を保ち,無秩序である.
- これらの六角形は五角形と七角形の単位で接続され,140K以下の高層で無形な氷の成長につながります.
- 結晶の氷に変換すると,最初の層は基板の六角対称性に合うように再構成されます.
- 構造上の欠陥は,領域の境界と積み重ねの欠陥として特定されました.
- これらの欠陥は,転移性立方体の氷の形成に寄与する.
結論:
- 最初の水層の構造は 氷の後の成長と段階に 重要な影響を及ぼします
- メタステーブルな無形と立方形の氷構造は,特定のインターフェイスの配置と欠陥によって形成されます.
- 氷の形成過程を制御する鍵となるものです 氷の形成過程を制御する鍵となるものです
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