Strong Anisotropic Interaction Controls Unusual Sticking and Scattering of CO at Ru(0001).
Strong Anisotropic Interaction Controls Unusual Sticking and Scattering of CO at Ru(0001).
复制标题
强各向异性相互作用控制 CO 在 Ru(0001) 上异常的粘附和散射
DOI：
10.1103/physrevlett.119.146101
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发表时间：
2017
影响因子：
8.6
通讯作者：
P. Saalfrank
中科院分区：
文献类型：
--
作者：
I. Loncaric;J.I. Juaristi;G. Füchsel;P. Saalfrank
在分子束实验中，经常观察到在低入射能量下的完全粘附和在较高能量下的宽角散射分布。尽管CO强烈地结合在Ru（0001）上，但散射的特征在于相当窄的角分布，并且即使在低入射能量下粘附也是不完全的。我们进行分子动力学模拟，占声子（和电子）的能量损失通道，在势能面上的第一性原理的电子结构计算，重现分子束实验的基础上。我们证明，上述不寻常的行为是一个非常强的旋转各向异性的分子表面相互作用势的结果。除了散射现象的解释，我们还讨论了我们的研究结果的影响，最近提出的前体状态的解吸和散射的CO从钌的作用。
Complete sticking at low incidence energies and broad angular scattering distributions at higher energies are often observed in molecular beam experiments on gas-surface systems which feature a deep chemisorption well and lack early reaction barriers. Although CO binds strongly on Ru(0001), scattering is characterized by rather narrow angular distributions and sticking is incomplete even at low incidence energies. We perform molecular dynamics simulations, accounting for phononic (and electronic) energy loss channels, on a potential energy surface based on first-principles electronic structure calculations that reproduce the molecular beam experiments. We demonstrate that the mentioned unusual behavior is a consequence of a very strong rotational anisotropy in the molecule-surface interaction potential. Beyond the interpretation of scattering phenomena, we also discuss implications of our results for the recently proposed role of a precursor state for the desorption and scattering of CO from ruthenium.