快速的分子内电荷转移与一个平面硬化的电子捐赠/接受分子
Toshitada Yoshihara1, Sergey I Druzhinin, Klaas A Zachariasse
1Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany.
Journal of the American Chemical Society
|July 9, 2004
概括
平面化 (FPP) 在激发状态下表现出快速的分子内电荷转移 (ICT). 高效的ICT不需要大分子运动,挑战了设计快速切换系统的先前假设.
科学领域:
- 摄影化学的使用.
- 分子动力学分子动力学
- 有机化学 有机化学
背景情况:
- 分子内电荷转移 (ICT) 是一个基本的光物理过程.
- 设计用于快速切换的分子需要了解ICT动态.
- 扭曲的分子内电荷转移 (TICT) 状态通常涉及显著的分子重组.
研究的目的:
- 为了研究平面分子化 (FPP) 的兴奋状态动态.
- 为了确定高效的ICT是否可以在没有大振幅运动的平面系统中发生.
- 为了比较FPP的ICT行为与其灵活的模拟物N-phenylpyrrole (PP).
主要方法:
- 时间分辨率光谱学用于研究激发状态动态.
- 溶剂极性研究以探测电荷转移特性.
- 对于不同电子状态的双极矩计算.
主要成果:
- 酸 (FPP) 在45°C下在乙烯化物中显示出快速 (12 ps) 可逆的ICT.
- FPP的ICT状态具有很大的二极子时刻 (13D),明显高于局部激发状态 (1D).
- FPP的ICT行为与柔性N-phenylpyrrole (PP) 的行为非常相似,表明平面结构中有效的电荷转移.
结论:
- 有效的分子内电荷转移到平面激发状态是可以实现的.
- 设计快速切换的ICT系统不需要大型分子运动,例如形成ICT状态的分子运动.
- 平面硬化分子为开发高效,快速的ICT系统提供了可行的平台.
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