Institute of Theoretical Physics and IQST, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
Institute of Theoretical Physics, Department of Theoretical Biophysics, Johannes Kepler University Linz, Altenberger Str. 69, 4040, Linz, Austria.
Nat Commun. 2022 May 25;13(1):2912. doi: 10.1038/s41467-022-30565-4.
The primary steps of photosynthesis rely on the generation, transport, and trapping of excitons in pigment-protein complexes (PPCs). Generically, PPCs possess highly structured vibrational spectra, combining many discrete intra-pigment modes and a quasi-continuous of protein modes, with vibrational and electronic couplings of comparable strength. The intricacy of the resulting vibronic dynamics poses significant challenges in establishing a quantitative connection between spectroscopic data and underlying microscopic models. Here we show how to address this challenge using numerically exact simulation methods by considering two model systems, namely the water-soluble chlorophyll-binding protein of cauliflower and the special pair of bacterial reaction centers. We demonstrate that the inclusion of the full multi-mode vibronic dynamics in numerical calculations of linear spectra leads to systematic and quantitatively significant corrections to electronic parameter estimation. These multi-mode vibronic effects are shown to be relevant in the longstanding discussion regarding the origin of long-lived oscillations in multidimensional nonlinear spectra.
光合作用的主要步骤依赖于激子在色素-蛋白质复合物（PPC）中的产生、传输和捕获。一般来说，PPC 具有高度结构化的振动光谱，结合了许多离散的内色素模式和准连续的蛋白质模式，具有相当强度的振动和电子耦合。由此产生的振子动力学的复杂性给建立光谱数据和基础微观模型之间的定量关系带来了重大挑战。在这里，我们通过考虑两个模型系统，即花椰菜水溶性叶绿素结合蛋白和细菌反应中心的特殊对，展示了如何使用数值精确的模拟方法来解决这一挑战。我们证明，在对线性光谱的数值计算中包含完整的多模振子动力学，会导致电子参数估计的系统且具有定量意义的修正。这些多模振子效应与多维非线性光谱中长寿命振荡起源的长期讨论有关。
