摘要
The internal conversion （IC） processes of chlorophyll a （chl-a） in solvents are studied based on the reduced density matrix theory. The IC times can be obtained by simulating the experimental fluorescence depletion spectra （FDS）. The calculated IC times of chl-a in ethyl acetate, tetrahydrofuran and dimethyl formamide are 141, 147, and 241 fs, respectively. The oscillation feature of the FDS results from the forward and backward transfer of the population between coupled electronic states. The effects of diabatic coupling between two electronic states on the IC time and the FDS are described. The influence of molecule-reservoir coupling on the IC time is also investigated.
基金
We would like to thank Dr. Y. Shi and Professor K. L. Han for providing the FDS data and useful discussions. K. Niu is grateful to Professor V. May for enlightening suggestions. This work was supported by the National Natural Science Foundation of China （No. 10674022 and No.20633070）.
