有机电子转移的外部和内部球体机制的连续性. 在偏磁性 (离子基) 自交换中,前体复合物的固态调制
Sergiy V Rosokha1, Jay K Kochi
1Department of Chemistry, University of Houston, Houston, Texas 77204, USA.
Journal of the American Chemical Society
|March 7, 2007
概括
观察到有机电子捐赠者和接受者的短暂前体复合体. 绝缘散体通过调节捐助者-接受者分离,桥接有机和无机电子转移概念来影响电子转移速率.
科学领域:
- 物理化学 物理化学
- 有机化学 有机化学
- 超分子化学 超分子化学
背景情况:
- 在化学和生物过程中,分子间电子转移是基本的.
- 了解前体复合物是控制电子转移速率的关键.
- 有机电子捐赠者 (D) 和接受者 (A) 形成过渡的基离离子对.
研究的目的:
- 在光谱和结构上表征有机电子捐赠者和接受者的短暂1:1前体复合物.
- 为了确定电子合元件 (HDA) 和马库斯重组能量 (lambda).
- 为了研究固体阻碍对电子传输速率的影响.
主要方法:
- 紫外可见和近红外 (NIR) 光谱学用于观察过渡复合体.
- 用X射线晶体学来确定共面 (pi-stacked) 关联体的结构.
- 电子合 (HDA) 的穆利肯-赫什分析.
- 马库斯关于重组能量的理论 (lambda).
- 分子轨道计算. 分子轨道计算.
主要成果:
- 确定了暂时的1:1前体复合物[D,D+*]和[A-*,A].
- 电子合元件 (HDA) 被量化,发现它们依赖于重的替代品.
- 捐赠者-接受者分离 (rDA) 的立体调制显著影响了电子转移速率.
- 在固态阻碍系统和不受阻碍系统中观察到不同的电子传输速率.
结论:
- 在控制有机系统中分子间电子转移速率方面,固体效应至关重要.
- 该研究提供了电子转移机制的统一观点,将有机和无机概念联系起来.
- 这些发现为设计具有量身定制的电子转移特性的分子提供了洞察力.
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