Al-Jaaidi Ali, Toldo Josene M, Barbatti Mario
Aix Marseille University, CNRS, ICR, Marseille, France.
UCBL, ENS de Lyon, CNRS, LCH, UMR 5182, Lyon Cedex 07, France.
J Comput Chem. 2025 Jan 5;46(1):e27547. doi: 10.1002/jcc.27547.
Diketopyrrolopyrroles (DPPs) have attracted attention for their potential applications in organic photovoltaics due to their tunable optical properties and charge-carrier mobilities. In this study, we investigate the excited-state dynamics of a DPP dimer using time-dependent density functional theory (TDDFT) and nonadiabatic molecular dynamics simulations. Our results reveal a near-barrierless hydrogen migration state intersection that facilitates ultrafast internal conversion with a lifetime of about 400 fs, leading to fluorescence quenching. Electronic density analysis along the relaxation pathway confirms a hydrogen atom transfer mechanism. These findings highlight the critical role of state intersections in the photophysical properties of DPP dimers, providing new insights for the design of functionalized DPP systems aimed at suppressing nonradiative decay for enhanced performance in photovoltaic applications.
由于其可调谐的光学性质和电荷载流子迁移率，二酮吡咯并吡咯（DPPs）在有机光伏领域的潜在应用引起了关注。在本研究中，我们使用含时密度泛函理论（TDDFT）和非绝热分子动力学模拟研究了DPP二聚体的激发态动力学。我们的结果揭示了一个近乎无势垒的氢迁移态交叉，它促进了超快的内转换，寿命约为400飞秒，导致荧光猝灭。沿弛豫路径的电子密度分析证实了氢原子转移机制。这些发现突出了态交叉在DPP二聚体光物理性质中的关键作用，为设计功能化DPP系统提供了新的见解，旨在抑制非辐射衰变以提高光伏应用中的性能。
