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光合作用原初过程中所存在的快速电子转移一般认为是电子由激发志单线态叶绿素(Donor)向醌分子(Acccptor)转移,近年来以卟啉和醌分子共价相连的分子体系摸拟原初过程的电子转移过程的研究非常活跃。虽然这类体系目前量子产率还很低,但是已为我们展示了这一模型体系的合理性。本文所报导是一种新型的电子给体和电子受体共价相连的体系即卟啉和硝基苯共价相连的分子体系。本文简述了该系列化合物的合成方法,详见文献[5]。着重讨论了它们的光物理行为包括吸收光谱,静志荧光光谱及毫微秒荧光光谱,及激发态寿命。所得结论是:这类化合物中在光幅射下存在着由激发志卟啉向硝基苯进行电子转移的过程,其规律几乎与卟啉—醌体系是一致的。但值得注意的是卟啉与硝基苯的相对构象对该过程有明显的影响。这种影响给我们的启示是:在以共价相连的电子给体和电子受体的分子体系设计中不但要考虑电子给体和电子受体间相对距离,共价链的种类,同时应考虑它们之间的相对取向,而后者往往被人们忽视。
Rapid electron transfer in the original photosynthesis process is generally believed that the electron is excited by the singlet-excited state of the chlorophyll (Donor) to the quinone molecule (Acccptor) transfer in recent years with porphyrin and quinone molecules covalently linked molecular system to simulate the original process The study of electron transfer process is very active. Although the quantum yield of such systems is still low, we have shown us the rationality of this model system. This article reports a new type of electron donor and electron acceptor covalently linked system that is a molecular system of porphyrin and nitrobenzene covalently linked. This article describes the synthesis of a series of compounds, as detailed in [5]. Their photophysical behavior is discussed, including absorption spectra, stationary fluorescence spectra and nanosecond fluorescence spectra, as well as excited state lifetime. The conclusion is: there is a process of electron transfer from excited chioporphyrin to nitrobenzene under light irradiation in this kind of compound, and its rule is almost the same with the porphyrin-quinone system. However, it is noteworthy that the relative conformation of porphyrin and nitrobenzene has a significant effect on the process. The implications of this influence are: In the molecular system design of covalently linked electron donors and electron acceptors, not only the relative distances between electron donors and electron acceptors, the types of covalent chains, but also the The relative orientation between them, which is often overlooked.