Theoretical Division , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States.
U.S. Army Research Laboratory , Aberdeen Proving Ground , Maryland 21005 , United States.
Chem Rev. 2020 Feb 26;120(4):2215-2287. doi: 10.1021/acs.chemrev.9b00447. Epub 2020 Feb 10.
Optically active molecular materials, such as organic conjugated polymers and biological systems, are characterized by strong coupling between electronic and vibrational degrees of freedom. Typically, simulations must go beyond the Born-Oppenheimer approximation to account for non-adiabatic coupling between excited states. Indeed, non-adiabatic dynamics is commonly associated with exciton dynamics and photophysics involving charge and energy transfer, as well as exciton dissociation and charge recombination. Understanding the photoinduced dynamics in such materials is vital to providing an accurate description of exciton formation, evolution, and decay. This interdisciplinary field has matured significantly over the past decades. Formulation of new theoretical frameworks, development of more efficient and accurate computational algorithms, and evolution of high-performance computer hardware has extended these simulations to very large molecular systems with hundreds of atoms, including numerous studies of organic semiconductors and biomolecules. In this Review, we will describe recent theoretical advances including treatment of electronic decoherence in surface-hopping methods, the role of solvent effects, trivial unavoided crossings, analysis of data based on transition densities, and efficient computational implementations of these numerical methods. We also emphasize newly developed semiclassical approaches, based on the Gaussian approximation, which retain phase and width information to account for significant decoherence and interference effects while maintaining the high efficiency of surface-hopping approaches. The above developments have been employed to successfully describe photophysics in a variety of molecular materials.
手性分子材料，如有机共轭聚合物和生物体系，其电子和振动自由度之间存在强耦合。通常，为了考虑激发态之间的非绝热耦合，模拟必须超越玻恩-奥本海默近似。实际上，非绝热动力学通常与激子动力学和光物理有关，涉及电荷和能量转移，以及激子解离和电荷复合。了解这些材料中的光诱导动力学对于提供激子形成、演化和衰减的准确描述至关重要。在过去几十年中，这个跨学科领域已经取得了显著的发展。新理论框架的制定、更有效和准确的计算算法的开发以及高性能计算机硬件的发展，将这些模拟扩展到了具有数百个原子的非常大的分子系统，包括对有机半导体和生物分子的大量研究。在这篇综述中，我们将描述最近的理论进展，包括表面跳跃方法中电子退相干的处理、溶剂效应的作用、平凡不可避免的交叉、基于跃迁密度的数据分析以及这些数值方法的高效计算实现。我们还强调了新开发的基于高斯近似的半经典方法，该方法保留了相位和宽度信息，以考虑显著的退相干和干涉效应，同时保持表面跳跃方法的高效率。上述发展已成功用于描述各种分子材料中的光物理。
