金属の吸附と粘着エネルギーは,MgO (MgO100) 上にある
Charles T Campbell1, David E Starr
1Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700, USA. campbell@chem.washington.edu
Journal of the American Chemical Society
|August 1, 2002
まとめ
MgO (MgO100) の金属吸収は,カロリメトリーを用いて研究されました. 吸収熱は金属の性質と相関し,2Dアイランドと3Dフィルムの両方の結合と膜形成の洞察を明らかにします.
科学分野:
- 表面科学とは,地表科学である.
- 材料化学 材料化学について
- アドソルプション現象
背景:
- 金属-MgO100) 相互作用を理解することは,薄膜の成長に不可欠です.
- MgO (MgO100) 上でのCu,Ag,Pbの吸収熱に関する以前の熱計測定は存在しています.
研究 の 目的:
- 測定された吸着熱を散発金属の性質と相関させる.
- 金属-MgO(100) 結合エネルギーと粘着性を調査する.
- 2次元 (2D) と3次元 (3D) の金属フィルムにおけるエリューシデート結合機構.
主な方法:
- Cu,Ag,Pbの吸収熱をMgO上でのカロメトリック測定100).
- 低カバーボンドエネルギーを推定するために,ペアウェイズ・ボンド・アディティビティ・モデルの適用.
- 大量金属の特性 (亜鉛化エネルギー,酸化物形成熱) との相関分析.
主要な成果:
- 低範囲の吸収熱は,初期粘着確率と島密度と相関し,一時的な移動先駆体モデルをサポートします.
- 金属-MgO ((100) 結合エネルギーは,低カバーで,大量亜鉛化エネルギーと相関し,欠陥における支配的な共性金属-Mg結合を示唆しています.
- 3Dフィルムの粘着エネルギーは,金属の亜鉛化エネルギーと大量酸化物形成熱と相関しており,金属-酸素および金属-Mg結合からの貢献を示しています.
結論:
- kovalent metal-Mg bondingは,MgO (MgO) の100) の欠陥のカバーが低い場合に顕著である.
- MgO (MgO100) の3D金属フィルムにおける界面結合は,金属と酸素の相互作用と,共性金属とMgの相互作用の両方を含む.
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