ポルフィリンテープの光物理学的特性
Hyun Sun Cho1, Dae Hong Jeong, Sung Cho
1Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea.
Journal of the American Chemical Society
|December 6, 2002
まとめ
新型溶融亜鉛 (Tn) のポルフィリンテープ (Tn) は,オートゴーナル配列と対照的に,急速な興奮状態形成と加速したリラックスを示しています. これらの性質は,電子や光学における応用を示唆しています.
科学分野:
- 超分子化学 超分子化学
- フォトフィジックスの光学
- マテリアルサイエンス 材料科学
背景:
- ポルフィリン配列は,そのユニークな光物理的性質のために研究されています.
- 溶融ポルフィリン構造は,新しい電子的,光学的特性を提供します.
研究 の 目的:
- 新しく融合したZn(II) ポルフィリン配列 (ポルフィリンテープ,Tn) の光物理学的性質を調査する.
- これらの融合配列の性質を正交のポルフィリン配列と比較する.
- ポルフィリンテープの潜在的応用を探求する.
主な方法:
- 静止状態と時間解像度のスペクトル測定.
- 理論的な分子軌道 (MO) 計算 (PPP-SCI).
主要な成果:
- ポルフィリンテープの吸収スペクトルは,色素数が増加するにつれて,IR領域にシフトします.
- 急速な興奮状態形成 (約. 500 fsのT2) を内部変換で,モノメリックZn (II) ポルフィリン (1.2 ps) よりも速い.
- 興奮状態のリラクゼーションは,エネルギーギャップ法によって説明されるポーフィリン単位 (T2ダイマーでは4.5psi,T6ヘクサマーでは0.3psi) の増加とともに加速する.
- ポルフィリンテープの最も低い興奮状態のワンニエ型エクシトンの特徴は,直接リンクされた配列のフレンケル型エクシトンとは違います.
結論:
- 溶融ポルフィリンテープは,直角配列とは異なるユニークな光物理的特性を有しています.
- 観測された性質は,融合した平面構造とエクシトンの行動に起因する.
- ポルフィリンテープは,電線,赤外線センサー,非線形光学材料などの応用の可能性を示しています.
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