ポラライゼーション・セレクティブ・アングル・レゾルトッド・赤外線ポンプ・プローブ・スペクトロスコーピーによる機能化されたアルキル・プラナー・モノレイヤの方向動力学
Jun Nishida1, Chang Yan1, Michael D Fayer1
1Department of Chemistry, Stanford University , Stanford, California 94305, United States.
Journal of the American Chemical Society
|September 27, 2016
まとめ
インタフェースの分子の動きを 研究するために 新しいスペクトロスコーピーを開発しました この方法は,レニウム機能化されたシロキサン単層の制限された外平面と複雑な内平面の方向ダイナミクスを明らかにした.
科学分野:
- 表面科学
- スペクトロスコーピー
- 物理化学
背景:
- 表面の分子ダイナミクスを理解することは多くのアプリケーションにとって不可欠です.
- SiO2上のアルキルシロキサン単層は,インターフェイス研究のためのモデルシステムです.
- レニウム金属カルボニルヘッドグループには 独特のスペクトロスコーピックハンドルがあります
研究 の 目的:
- インタフェースの指向ダイナミクスを探査するための新しいスペクトロスコピーの技術を開発し,適用する.
- リニウム機能化されたシロキサン単層のピコ秒方向の緩和を調査する.
- 外平面と内平面の両方の方向相関関数を抽出して分析する.
主な方法:
- 偏光選択角度解像度の赤外線ポンプ探査スペクトロスコーピーを開発した.
- 時間の平均化による赤外線直線二極化測定と組み合わせた.
- 複数のインシデントアングルと,最近開発されたモデル独立分析の理論的枠組みを使用した.
主要な成果:
- モノレイヤー-エアインターフェースのピコ秒方向の緩解が特徴です.
- 双方向の角分布で非常に制限された外平面のヘッドグループ運動を明らかにした.
- 慣性,揺れ (~3 ps),ランダム化 (~25 ps) ダイナミクスを含む有意な平面内運動を観測した.
結論:
- 開発されたスペクトロスコピーは,インタフェースの複雑な指向ダイナミクスを成功裏に探査します.
- レーニウムヘッドグループには 異なった外平面と内平面の リラックス行動があります
- この発見は,機能化された単層における分子運動の性質についての洞察を提供します.
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