在超级交换和跳跃之间进行符合规格的关闭切换,在基于oligo-p-phenylene的分子电线内跳转
Emily A Weiss1, Michael J Tauber, Richard F Kelley
1Center for Nanofabrication and Molecular Self-Assembly and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|August 18, 2005
概括
捐赠者-桥梁-接受器系统中的电荷重组显示出明显的超级交换和跳跃行为. 温度的影响通过影响分子构造和超交换合来加剧重组率.
科学领域:
- 摄影化学的使用.
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 捐赠者-桥梁-接受者 (D-B-A) 系统对于电荷转移研究至关重要.
- 了解电荷重组 (CR) 机制是设计高效光电子材料的关键.
研究的目的:
- 研究D-B-A系统中电荷重组的温度依赖性.
- 阐明CR中超交换,跳跃和分子构造之间的相互作用.
主要方法:
- 合成具有不同p-烯桥长度的D-B-A系统 (n=1-4).
- 取决于温度的电荷重组测量.
- 磁场效应用于探测超交换合器 (V(DA)).
主要成果:
- 观察到不同区域的超级交换和热激活跳跃.
- 在较长的桥梁系统 (n=3,4) 中,与分子平面化相关的CR的量化激活障碍.
- 由于在更高的温度下发生的形状变化,证明了CR的负激活.
结论:
- 分子构造显著影响电荷重组路径和速率.
- 超交换合是由分子构成调节的,影响CR效率.
- CR通过特定的形状和有利的能量路径进行,受温度的影响.
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