Singlet photochemistry in model photosynthesis: Identification of charge separated intermediates by Fourier transform and CW-EPR spectroscopies
Singlet photochemistry in model photosynthesis: Identification of charge separated intermediates by Fourier transform and CW-EPR spectroscopies
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模型光合作用中的单线态光化学：通过傅里叶变换和 CW-EPR 光谱鉴定电荷分离中间体
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
A. Moore
中科院分区：
文献类型：
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作者：
K. Hasharoni;H. Levanon;Jau Tang;M. Bowman;J. Norris;D. Gust;T. Moore;A. Moore
本文用选择性激光激发的傅里叶变换和连续波电子顺磁共振研究了类胡萝卜素-卟啉-二醌四元体系的光激发态的分子内电子转移。结果表明，电子转移发生从单重态的卟啉组分产生的终端苯醌自由基阴离子和类胡萝卜素自由基阳离子。该四分子可以保持电荷分离状态相当长的一段时间（{约} 1 {mu}s），允许短寿命的自由基的特性。醌自由基阴离子的衍生物样光谱及其对微波脉冲转角的依赖性表明，电子转移通过单重态进行。
Intramolecular electron transfer from the photoexcited state of a carotenoid-porphyrin-diquinone tetrad was studied by selective laser excitation with both Fourier transform and CW EPR spectroscopies. It is shown that the electron transfer occurs from the singlet state of the porphyrin constituent to produce the terminal benzoquinone radical anion and the carotenoid radical cation. This tetrad molecule can maintain the charge-separated state for a substantial period of time ({approximately} 1 {mu}s), allowing the characterization of the short-lived radicals. The derivative-like spectrum of the quinone radical anion and its dependence on the turning angle of the microwave pulse indicates that electron transfer proceeds via the singlet state.