Laboratory of Computational Chemistry and Biochemistry, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
Chemphyschem. 2013 May 10;14(7):1314-40. doi: 10.1002/cphc.201200941.
Understanding the fate of an electronically excited molecule constitutes an important task for theoretical chemistry, and practical implications range from the interpretation of atto- and femtosecond spectroscopy to the development of light-driven molecular machines, the control of photochemical reactions, and the possibility of capturing sunlight energy. However, many challenging conceptual and technical problems are involved in the description of these phenomena such as 1) the failure of the well-known Born-Oppenheimer approximation; 2) the need for accurate electronic properties such as potential energy surfaces, excited nuclear forces, or nonadiabatic coupling terms; and 3) the necessity of describing the dynamics of the photoexcited nuclear wavepacket. This review provides an overview of the current methods to address points 1) and 3) and shows how time-dependent density functional theory (TDDFT) and its linear-response extension can be used for point 2). First, the derivation of Ehrenfest dynamics and nonadiabatic Bohmian dynamics is discussed and linked to Tully's trajectory surface hopping. Second, the coupling of these trajectory-based nonadiabatic schemes with TDDFT is described in detail with special emphasis on the derivation of the required electronic structure properties.
理解一个受电子激发的分子的命运是理论化学的一项重要任务，其实际应用范围从毫微微秒和飞秒光谱学的解释到光驱动分子机器的开发、光化学反应的控制以及捕获太阳能的可能性。然而，在描述这些现象时涉及到许多具有挑战性的概念和技术问题，例如 1）众所周知的 Born-Oppenheimer 近似的失效；2）需要准确的电子性质，如势能面、激发核力或非绝热耦合项；以及 3）描述光激发核波包动力学的必要性。本综述概述了目前解决第 1）和第 3）点的方法，并展示了如何使用含时密度泛函理论 (TDDFT) 及其线性响应扩展来解决第 2）点。首先，讨论 Ehrenfest 动力学和非绝热 Bohmian 动力学的推导，并将其与 Tully 的轨迹表面跳跃联系起来。其次，详细描述了这些基于轨迹的非绝热方案与 TDDFT 的耦合，特别强调了所需电子结构性质的推导。
