ポリマーマトリックスにおけるダイアリレチンの単一分子の光色化
Tuyoshi Fukaminato1, Tohru Umemoto, Yasuhide Iwata
1Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan.
Journal of the American Chemical Society
|April 17, 2007
まとめ
光フォトスイッチング分子は,固体ポリマーにおいて独特の振る舞いを示し,典型的な指数分布から逸脱する. これは,ポリマーマトリックス環境の影響を受けた光子依存反応機構を示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- フォトケミストリー フォトケミストリー
- 単一分子スペクトロスコピーは,単一分子スペクトロスコピーを用います.
背景:
- フォトスイッチング分子には,光ユニット (ペリレンビシミド) とスイッチングユニット (ダイリエレタン) が結合されています.
- 異なるポリマーマトリックスにおけるそれらの振る舞いを理解することは,アプリケーションにとって極めて重要です.
研究 の 目的:
- 新種のフォトスイッチング分子における単一分子フォトクロミック反応を調査する.
- 分子スイッチングダイナミクスに対するポリマーマトリックス硬さの影響を分析する.
主な方法:
- ペリレン・ビシミド・ダイアリレチンの光交換分子の調製.
- 様々なポリマーマトリックス (Zeonex,PMMA,PNBMA) で単分子光測定を行いました.
- 光灯のオン/オフ時間分布の分析.
主要な成果:
- 光灯のオン/オフ時間は,硬質ポリマー (Zeonex, PMMA) の指数分布から逸脱し,ピークを示した.
- ソフトポリマー (PnBMA) で指数関数分布が観察されました.
- 異常な分布は,不一定な量子産量と光子依存反応を示している.
結論:
- ポリマーマトリクスは,フォトスイッチングのダイナミクスに大きな影響を与えます.
- 多局所最小値モデルは,分子スイッチングに関する観測された環境効果を説明します.
関連する概念動画
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