We combined the electronic structure calculations and OM2(orthogonalization model 2)/MRCI nonadiabatic surface-hopping dynamics simulations to scrutinize the photoisomerization mechanisms of cis-stilbene. The static electronic structure calculations showed that the irradiation of cis-stilbene populates the bright S₁ state and we obtained three S₁/S₀ conical intersections (CIs) and proposed two nonadiabatic decay channels that efficiently de-excited to the ground state. In the first pathway, once excited to the S₁ state, the cis-stilbene proceeds along S₁ potential energy surface. Then, the molecule encounters S1S0-C CI, from which the system decays to S₀ state. The other pathway involves the S1S0-D CI from where the S₁ system hops to the ground state. In our simulations, we acquired cis, trans and DHP (4a,4b-dihydrophenanthrene) products and the ratio is estimated as 42:48:7. The present work show that the combination of electronic structure calculations and OM2/MRCI nonadiabatic dynamics can give detailed photochemical and photophysical information of stilbene systems.

我们将电子结构计算与OM2（正交化模型2）/ MRCI非绝热表面跳跃动力学模拟相结合，研究了顺二苯乙烯的光异构化机理。静态电子结构计算表明，顺-二苯乙烯的辐照使明亮的S ₁状态充满，我们获得了三个S ₁ / S ₀圆锥形交叉点（CIs），并提出了两个非绝热衰变通道，可以有效地将其激发为基态。在第一个途径中，一旦激发到S ₁状态，顺式-二苯乙烯就沿着S ₁前进势能面。然后，分子遇到S1S0-C CI，系统从中衰减到S ₀状态。另一条路径涉及S1S0-D CI，S ₁系统从此处跳至基态。在我们的模拟中，我们获得了顺式，反式和DHP（4a，4b-二氢菲）产物，该比例估计为42：48：7。目前的工作表明电子结构计算和OM2 / MRCI非绝热动力学的结合可以提供详细的光化学和光物理信息的系统。