Abramavicius Darius, Mukamel Shaul
Chemistry Department, University of California Irvine, California 92697-2025, USA.
J Phys Chem B. 2009 Apr 30;113(17):6097-108. doi: 10.1021/jp811339p.
Electronic excitations and the optical properties of the photosynthetic complex PSI are analyzed using an effective exciton model developed by Vaitekonis et al. [Photosynth. Res. 2005, 86, 185]. States of the reaction center, the linker states, the highly delocalized antenna states and the red states are identified and assigned in absorption and circular dichroism spectra by taking into account the spectral distribution of density of exciton states, exciton delocalization length, and participation ratio in the reaction center. Signatures of exciton cooperative dynamics in nonchiral and chirality-induced two-dimensional (2D) photon-echo signals are identified. Nonchiral signals show resonances associated with the red, the reaction center, and the bulk antenna states as well as transport between them. Spectrally overlapping contributions of the linker and the delocalized antenna states are clearly resolved in the chirality-induced signals. Strong correlations are observed between the delocalized antenna states, the linker states, and the RC states. The active space of the complex covering the RC, the linker, and the delocalized antenna states is common to PSI complexes in bacteria and plants.
利用Vaitekonis等人[《光合作用研究》2005年，86卷，185页]开发的有效激子模型，对光合复合物PSI的电子激发和光学性质进行了分析。通过考虑激子态密度的光谱分布、激子离域长度以及反应中心的参与比，在吸收光谱和圆二色光谱中识别并指定了反应中心态、连接态、高度离域的天线态和红色态。在非手性和手性诱导的二维（2D）光子回波信号中识别出了激子合作动力学的特征。非手性信号显示出与红色态、反应中心态和整体天线态相关的共振以及它们之间的传输。连接态和离域天线态在光谱上重叠的贡献在手性诱导信号中得到了清晰的分辨。观察到离域天线态、连接态和反应中心态之间存在强相关性。覆盖反应中心、连接态和离域天线态的复合物的活性空间是细菌和植物中PSI复合物共有的。
