EXCITON COHERENT MIGRATION AND TRAPPING IN PHOTOSYNTHESIS OF GREEN PLANTS
高等植物体内激子相干迁移与俘获

A new three-dimensional regular arrangement model of pigment molecules with fixed spatial orientation was constructed according to the researches on photosynthetic membranes. Based on the model and generalized-master-equation (GME) theory of excitation transfer, we advanced a lattice theory of exciton coherent migration and trapping in the photosynthesis of green plants under the conditions of low excitation for the first time. The new theory has received some support from fluorescence measurements done on chloroplasts with different photochemical states of reaction center(RC). The relations of fluorescence quantum yield, steady-state energy-transfer rates and luminescence intensities to the concentration of reduced RC, exciton lifetimes and the half-widiths of chlorophylls' absorption and emission spectra were investigated hy model calculations of above theory in order to illustrate the effects of exciton coherence on complete process of energy transport and trapping. It was also indicated that coherence is a possible factor to limit exciton lifetimes in vivo.