Vibrational Excitation in Gas-Surface Collisions of CO with Au(111): A First-Principles Nonadiabatic Dynamics Study

The scattering of CO from Au(111) is an important benchmark process to understand the energy transfer dynamics of molecular collisions on metal surfaces. Although abundant experimental data are available, realistic nonadiabatic dynamics simulations for this system have not become possible until very recently. Especially, the observation of the direct vibrational excitation of CO(v = 0) remains unexplained by any theory. Here, we investigate the nonadiabatic dynamics of CO(v = 0) scattering from Au(111) using an independent electron surface hopping method based on a first-principles-determined effective Hamiltonian. The measured rotational state distributions and vibrational excitation probabilities are reproduced well by our calculations. Moreover, our results identify that not only a direct electron–vibration coupling but also an indirect electron-mediated translation–vibration coupling could contribute to the vibrational excitation of CO.