Zhang Yaolong, Maurer Reinhard J, Guo Hua, Jiang Bin
Hefei National Laboratory for Physical Science at the Microscale , Department of Chemical Physics , University of Science and Technology of China , Hefei , Anhui 230026 , China . Email:
Department of Chemistry and Centre for Scientific Computing , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK . Email:
Chem Sci. 2018 Nov 8;10(4):1089-1097. doi: 10.1039/c8sc03955k. eCollection 2019 Jan 28.
The breakdown of the Born-Oppenheimer approximation gives rise to nonadiabatic effects in gas-surface reactions at metal surfaces. However, for a given reaction, it remains unclear which factors quantitatively determine whether these effects measurably contribute to surface reactivity in catalysis and photo/electrochemistry. Here, we systematically investigate hot electron effects during H scattering from Ag(111) using electronic friction theory. We combine first-principles calculations of tensorial friction by time-dependent perturbation theory based on density functional theory and an analytical neural network representation, to overcome the limitations of existing approximations and explicitly simulate mode-specific nonadiabatic energy loss during molecular dynamics. Despite sizable hot-electron-induced energy loss, no measurable nonadiabatic effects can be found for H scattering on Ag(111). This is in stark contrast to previous reports for vibrationally excited H scattering on Cu(111). By detailed analysis of the two systems, we attribute this discrepancy to a subtle interplay between the magnitude of electronic friction along intramolecular vibration and the shape of the potential energy landscape that controls the molecular velocity at impact. On the basis of this characterization, we offer guidance for the search of highly nonadiabatic surface reactions.
玻恩-奥本海默近似的失效会在金属表面的气-固反应中产生非绝热效应。然而，对于给定的反应，哪些因素定量地决定了这些效应是否对催化以及光/电化学中的表面反应活性有显著贡献仍不清楚。在此，我们使用电子摩擦理论系统地研究了H从Ag(111)表面散射过程中的热电子效应。我们将基于密度泛函理论的含时微扰理论对张量摩擦的第一性原理计算与解析神经网络表示相结合，以克服现有近似方法的局限性，并在分子动力学过程中明确模拟特定模式的非绝热能量损失。尽管热电子引起的能量损失可观，但对于H在Ag(111)表面的散射，未发现可测量的非绝热效应。这与之前关于振动激发的H在Cu(111)表面散射的报道形成鲜明对比。通过对这两个系统的详细分析，我们将这种差异归因于沿分子内振动的电子摩擦大小与控制碰撞时分子速度的势能面形状之间的微妙相互作用。基于这一特征描述，我们为寻找高度非绝热的表面反应提供了指导。
