Although a multitude of theoretical studies exist on light-harvesting complex 2 (LH2), less is known about the light-harvesting complex 3 (LH3) of similar ring-like structure. In a comparative study of three system, i.e., the LH2 protein-pigment aggregate of the purple bacterium Rhodospirillum molischianum as well as for the LH2 and LH3 complexes of Rhodoblastus acidophilus the similarities and the differences in the excitonic system were analyzed. To this end, the systems have been studied in a multi-scale approach that combines molecular dynamics simulations with quantum chemistry calculations and quantum dynamics. Along the ground-state molecular dynamics trajectories, the excited energy gaps were determined in a quantum mechanics/molecular mechanics hybrid fashion. Based on the simulations, spectral densities, absorption spectra and exciton dynamics have been determined. After correcting for some shortcoming in the absorption spectra, the exciton dynamics within and between the ring systems have been determined and discussed.

尽管对光收集复合物2（LH2）进行了大量的理论研究，但对类似环状结构的光收集复合物3（LH3）知之甚少。在三个系统的比较研究中，即紫色细菌Mhodospirillum molischianum的LH2蛋白质-色素聚集体，以及嗜酸Rhodoblastus acidophilus的LH2和LH3复合物分析了激子系统的异同。为此，已经以多尺度方法研究了该系统，该方法将分子动力学模拟与量子化学计算和量子动力学相结合。沿着基态分子动力学轨迹，以量子力学/分子力学的混合方式确定了激发能隙。基于模拟，确定了光谱密度，吸收光谱和激子动力学。在纠正了吸收光谱中的一些缺陷之后，已经确定并讨论了环系统内部和环系统之间的激子动力学。