Multi-dimensional mixed quantum–classical description of the laser-induced desorption of molecules
Multi-dimensional mixed quantum–classical description of the laser-induced desorption of molecules
复制标题
激光诱导分子解吸的多维混合量子经典描述
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
A. Gross
中科院分区：
文献类型：
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作者：
C. Bach;T. Klüner;A. Gross
采用量子-经典混合方法模拟了激光诱导表面脱附过程。在这种方法中，原子核的运动被经典地描述，而电子被量子力学地处理。自洽地考虑了原子核和电子之间的反馈。该方法的计算效率允许解吸过程的更现实的多维处理。我们将这种方法应用于NO从NiO（100）的激光诱导脱附，使用来自从头算量子化学计算的两态二维势能面;我们将该势能面扩展到七个维度，采用物理上合理的模型势。通过与相同势能面上跳跃波包计算的比较，验证了本文方法的有效性。我们专注于脱附NO分子的速度，旋转和振动分布。此外，我们模型的能量转移到衬底的表面振荡器。包括反冲过程中的模拟脱附动力学有决定性的影响，就速度和旋转分布而言。特别是，双峰的速度分布中观察到的低维和在实验中消失在一个高维的治疗。
A mixed quantum–classical method for the simulation of laser-induced desorption processes at surfaces is implemented. In this method, the nuclear motion is described classically, while the electrons are treated quantum mechanically. The feedback between nuclei and electrons is taken into account self-consistently. The computational efficiency of this method allows a more realistic multi-dimensional treatment of desorption processes. We apply this method to the laser-induced desorption of NO from NiO(100) using a two-state two-dimensional potential energy surface derived from ab initio quantum chemical calculations; we extend this potential energy surface to seven dimensions employing a physically reasonable model potential. By comparing our method to jumping wave-packet calculations on exactly the same potential energy surface we verify the validity of our method. We focus on the velocity, rotational, and vibrational distributions of the desorbing NO molecules. Furthermore, we model the energy transfer to the substrate by a surface oscillator. Including recoil processes in the simulation has a decisive influence on the desorption dynamics, as far as the velocity and rotational distribution is concerned. In particular, the bimodality in the velocity distribution observed in low dimensions and in the experiment disappears in a high-dimensional treatment.