Coane Colin V, Romanelli Marco, Dall'Osto Giulia, Di Felice Rosa, Corni Stefano
Department of Chemical Sciences, University of Padova, via Marzolo 1, Padova, Italy.
Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, 90089, USA.
Commun Chem. 2024 Feb 15;7(1):32. doi: 10.1038/s42004-024-01118-1.
Electronic Energy Transfer (EET) between chromophores is fundamental in many natural light-harvesting complexes, serving as a critical step for solar energy funneling in photosynthetic plants and bacteria. The complicated role of the environment in mediating this process in natural architectures has been addressed by recent scanning tunneling microscope experiments involving EET between two molecules supported on a solid substrate. These measurements demonstrated that EET in such conditions has peculiar features, such as a steep dependence on the donor-acceptor distance, reminiscent of a short-range mechanism more than of a Förster-like process. By using state of the art hybrid ab initio/electromagnetic modeling, here we provide a comprehensive theoretical analysis of tip-enhanced EET. In particular, we show that this process can be understood as a complex interplay of electromagnetic-based molecular plasmonic processes, whose result may effectively mimic short range effects. Therefore, the established identification of an exponential decay with Dexter-like effects does not hold for tip-enhanced EET, and accurate electromagnetic modeling is needed to identify the EET mechanism.
发色团之间的电子能量转移（EET）在许多天然光捕获复合物中至关重要，是光合植物和细菌中太阳能汇聚的关键步骤。近期涉及在固体基底上支撑的两个分子之间进行EET的扫描隧道显微镜实验，探讨了环境在介导自然结构中这一过程时所起的复杂作用。这些测量结果表明，在这种条件下的EET具有特殊特征，例如对供体 - 受体距离的强烈依赖性，这让人联想到一种短程机制，而非类福斯特过程。通过使用最先进的混合从头算/电磁建模方法，我们在此对尖端增强EET进行了全面的理论分析。特别是，我们表明这一过程可理解为基于电磁的分子等离子体过程的复杂相互作用，其结果可能有效地模拟短程效应。因此，已确立的具有类德克斯特效应的指数衰减识别方法不适用于尖端增强EET，需要精确的电磁建模来确定EET机制。
