电子捐赠-桥梁-接受分子与桥梁基氧化基:第三次旋转对电荷和旋转转移动力学的影响
Erin T Chernick1, Qixi Mi, Richard F Kelley
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|March 30, 2006
概括
将稳定基连接到供体 - 桥梁 - 接受器系统中,可以控制电荷和自旋动力学. 一个基氧化物基因减缓了电荷重组在三基基中,与二基基不同,并诱导了旋转极化.
科学领域:
- 光化学和光物理学
- 旋转化学 旋转化学
- 分子电子学分子电子学
背景情况:
- 捐赠者-桥梁-接受器 (D-B-A) 系统对于控制电荷和旋转转移至关重要.
- 稳定基提供了一个在D-B-A架构中调节这些动态的手段.
研究的目的:
- 研究将稳定的氧化 (NN*) 基添加到D-B-A系统对电荷和旋转转移动力学的影响.
- 了解NN*基如何影响光生成的三基态及其重组途径.
主要方法:
- 一个D-B-A系统的合成与一个与p-methoxyaniline (MeOAn),4-(N-piperidinyl) naphthalene-1,8-dicarboximide (6ANI),一个基氧化物 (NN*),和naphthalene-1,8:4,5-bis(dicarboximide) (NI) 功能化的基桥.
- 时间分辨率光学光谱检测电荷转移和重组.
- 电子磁共振 (EPR) 光谱检测旋转动力学和极化.
主要成果:
- 与相似的二基相比,NN*基在光生成的三基状态下显著减缓了电荷重组.
- MeOAn基离子和NI基离子之间的旋转-旋转交换相互作用不受NN*的影响.
- NN*加速了激素对系统间交叉,并在电荷重组产物中诱导了显著的旋转极化,这归因于具有三重状态的抗铁磁合.
结论:
- 附加像NN*这样的稳定基提供了一个有效的策略来控制D-B-A系统中的电荷重组率.
- 在产品状态下对NN*的观察到的旋转极化突出显示了一种独特的旋转动态路径,由与三重状态的合驱动.
- 这项研究表明了将稳定基结纳入分子系统中先进的旋转操纵的潜力.
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