给体-受体体系分子内光致电子转移反应研究

对一类以９，１０－二甲氧基蒽为给体，双酚Ａ为连接链连接不同受体的电子给体－受体体系，通过单光子计数法测定荧光寿命，计算了体系的光致电子转移反应速率常数；通过测定氧化还原电位，计算出各电子给体－受体体系电子转移反应的自由能变化。并根据电子转移反应理论对光致电子转移速率常数与自由能变化关系进行了理论计算分析，发现本文各体系的光致电子转移速率常数的实验值与电子转移反应理论曲线吻合得比较好，同时也揭示在该

Intramolecular Photoinduced Electron Transfer in Donor-BA-Acceptor Systems

Intramolecular photoinduced electron transfer in a series of donor-acceptor systems consisting of 9,10-dimethoxyanthracene and differently substituted benzoic esters have been investigated. From fluorescence life-time measurements using single-photon counting technique, the rate constants of electron transfer ket were obtained. The free energy changes ΔG of electron transfer from the first excited state of 9,10-dimethoxyanthracene were obtained by determining the redox potentials of the donor and the acceptors and the first excitation energy. The dependence of photoinduced electron transfer rates on the exothermicity of the reaction has been studied by the theoretical analysis based on quantum mechanical treatments of electron transfer. The results show that the experimental values coincide well with that obtained by theoretical calculations. Although the inverted region is not seen in our results, the present treatment predicts that the inverted region would be observed at still lower values of ΔG than so far examined.