在捐赠-结合桥接收分子内,对自旋依赖的电荷重组机制的溶剂控制
Emily A Weiss1, Michael J Ahrens, Louise E Sinks
1Center for Nanofabrication and Molecular Self-Assembly, Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|August 5, 2004
概括
现亚--烯二胺 (PTZ-PDI) 系统的分子线行为随着溶剂极性而变化. 从烯切换到MTHF逆转了对基离子对重组的磁场效应,改变了电荷重组路径.
科学领域:
- 摄影化学的使用.
- 分子电子学分子电子学
- 超分子化学 超分子化学
背景情况:
- 具有p-烯桥梁的捐赠者桥接收器 (DBA) 系统表现出分子电线特性.
- 激素离子对 (RP) 重组动力学对外部磁场敏感,允许测量单元三元分裂 (2J).
- 供体和受体位点之间的电子合 (VDA^2) 影响RP重组和磁场效应 (MFE).
研究的目的:
- 为了研究溶剂极性对PTZ-(Ph) n-PDI分子线中的电荷重组机制的影响.
- 为了确定磁场效应 (MFE) 对RP群体是否可以通过溶剂环境调节.
- 了解分子结构,溶剂效应和电荷重组路径之间的相互作用.
主要方法:
- PTZ-{Ph) n-PDI供体-桥梁-接受体系统的合成和特征.
- 用多和2甲基四水 (MTHF) 进行光谱研究,以监测RP种群.
- 测量磁场效应 (MFE) 以探测单元三元分裂和重组路径.
主要成果:
- 寡合的p-phenylene桥作为一个分子电线,从指数转变为线性距离依赖RP重组的功能.
- 当将溶剂从二烯切换到PTZ+*-(Ph) 4-PDI-*和PTZ+*-(Ph) 5-PDI-*的更极性MTHF时,观察到RP群体上的MFE的"反转".
- MFE逆转表明单重 (CRS) 和三重 (CRT) 电荷重组路径的相对贡献发生了变化.
结论:
- 在PTZ-PDI分子电线中的电荷重组机制对周围的溶剂环境敏感.
- 像MTHF这样的极性溶剂可以稳定RP状态,有利于单电荷重组 (CRS) 并改变MFE.
- 这项研究强调了环境因素在调整分子电线功能和电荷传输过程中的重要性.
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