光合捕光天线中激子参与传能的理论研究

The absorption, storage and transfer of the light energy by light-harvesting antennae are fundamental and important processes in photosynthesis. These processes are achieved through the excitation and decay of local or coherent excitonic state on pigment molecule clusters in light-harvesting complexes. Because knowing of the high resolution spatial structures for some of light-harvesting antennae and a large number of single molecule spectroscopy data, the mechanism of the processes is understood gradually, but in most cases, knowledge about the exciton level structure and its characteristic parameters is far from complete. The position arrangements of pigment molecules in light-harvesting complexes, orientations of local dipole moments on every pigment molecules, static disorder, thermal motion, dynamic structures, also the number of pigment molecules in one light-harvesting antenna, etc. are all key factors in photosynthesis. Combined with the structural informations of light-harvesting complexes, spectroscopy data, and the experimental work in our research group, we establish the theoretical models to calculate and analyse every steps of the light energy transfer in light-harvesting antennae. Through deep understanding of the relationship between the structure and function of light-harvesting complexes on atomic level, we hope to more deeply reveal the mechanism of light energy transfer in photosynthesis, understand how to control the absorption, storage and transfer of the light energy, also design the theoretical models of light-harvesting antennae for some special needs, and test it experimentally.

光能被捕光天线所吸收、储存和传递是光合作用中起关键作用的基本过程。这些过程是通过捕光天线中色素分子团簇上局域和相干激子态的激发和回落来实现的。由于有了部分捕光天线高分辨率空间结构和大量单分子光谱的实验数据,使这些过程的机理得以逐步明了, 但还远远不够完整。捕光天线中色素分子空间位置排列、色素分子上局域偶极矩取向排列、静态无序、热运动、动态结构、捕光天线中色素分子的个数等, 都是光合作用中关键性因素。综合已知的捕光天线结构信息和光谱实验数据，同时结合我们研究组的实验工作,建立相应的理论模型，计算分析从光能吸收到其被传输到反应中心的详细过程。在原子水平上进一步研究捕光天线结构与功能的关系，期望更深入地揭示光合作用高效传能的微观机理, 阐明光能吸收、储存和传递过程的调节和控制原理, 以及设计出具有特殊性质的捕光天线系统理论模型，并试图获得实验的验证。