Wavepacket dynamics of ultrafast reactions with relaxation

从理论上研究了NO在Pt（111）表面上的光脱附动力学过程中振动弛豫的影响。虽然这个系统已经在许多以前的工作中进行了研究，NO伸缩振动的弛豫由于与金属中的电子空穴对的相互作用还没有包括在传统的模型。虽然吸附在金属表面上的双原子分子的第一激发振动态的弛豫寿命通常在0.1-1 ps范围内，但NO的脱附动力学在约1 ps内完成。因此，可以认为，在脱附过程中，振动弛豫可以影响该伸缩模的振动状态。我们用密度矩阵的时间传播描述了脱附动力学。振动弛豫的影响，包括通过使用一个雷德菲尔德的模型。我们还研究了从头算方法的动力学计算参数的有效性。因此，我们得到了物理上合理的结果的脱附概率，平均平移能，和脱附NO分子的振动态分布。

The effect of vibrational relaxation on the photodesorption dynamics of NO from a Pt(111) surface has been investigated theoretically. Although this system has been studied in many previous works, the relaxation of NO stretching vibration due to the interaction with electron-hole pairs in metals has not been included in conventional models. Although the relaxation lifetimes of the first-excited vibrational state of diatomic molecules adsorbed on metal surfaces are generally in the range 0.1-1 ps, the desorption dynamics of NO complete in about 1 ps. Therefore, it is considered that the vibrational relaxation can influence the vibrational state of this stretching mode during the desorption process. We described the desorption dynamics by using the time propagation of the density matrix. The effects of vibrational relaxation were included by using a Redfleld-like model. We also investigated the validity of the parameters for dynamical calculations by ab initio methods. As a result, we obtained physically reasonable results for the desorption probability, the mean translational energy, and the vibrational state distribution for the desorbed NO molecules.