INTERMOLECULAR ELECTRON TRANSFER IN PORPHYRIN DIMERS

施主和受主之间电子耦合的性质 在电子转移过程中， 从而确定这些反应的速率和产率。 它 很可能供体和受体之间的物理耦合也 在这样的系统中的电子耦合中起着相关的作用。 在 为了研究物理耦合对 电子耦合，因此电子转移速率常数，我们 正在研究一种化合物， 转移反应基本上保持不变，但物理 电子转移配偶体之间的偶联不同。 我们特别 合成了一系列金属卟啉体系， 电子供体和受体对通过一系列 苯环间隔基，其共价连接至 卟啉环或轴向配位到包含在卟啉环中的金属。 卟啉环 正向和反向电子转移速率 已经通过飞秒泵浦-探测光谱和TCSPC测量 (time相关单光子计数）。 我们的结论是 电子转移速率常数确实存在差异 其反映了供体和受体的物理耦合 部分。

The nature of the electronic coupling between donors and acceptors in electron transfer processes is an important consideration in determining the rates and therefore the yields of such reactions. It is likely that the physical coupling between donors and acceptors also plays a pertinent role in the electronic coupling in such systems. In order to investigate the effect of the physical coupling on the electronic coupling, hence the electron transfer rate constants, we are studying compounds in which the driving force for electron transfer reaction remains essentially constant but the physical coupling between electron transfer partners differs. Specifically, we have synthesized a series of metallo-porphyrin systems which consist of an electron donor and acceptor pair linked by a series of phenyl-ring spacers which are either covalently linked to the porphyrin ring or coordinated axially to the metal contained in the porphyrin ring. The rates for forward and reverse electron transfer have been measured by femtosecond pump-probe spectroscopy and TCSPC (time correlated single photon counting). We have concluded that there is, indeed a difference in the electron transfer rate constants which reflects the physical coupling of the donor and acceptor moieties.