Steric effects in scattering and adsorption of NO at Ag(111)
Steric effects in scattering and adsorption of NO at Ag(111)
复制标题
Ag(111) 上 NO 散射和吸附的空间效应
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
S. Stolte
中科院分区：
文献类型：
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作者：
A. Kleyn;E. W. Kuipers;M. G. Tenner;S. Stolte
散射实验已经使用定向光束的NO分子在Π/2-电子基态和J=MJ= 1/2。在直接非弹性散射中，我们观察到，随着分子的O-端优先朝向表面取向，角分布从镜面方向朝向表面偏移。在捕获/解吸的实验中，似乎对朝向表面的O-端的捕获增强。这两个结果都可以解释为O端向下的分子比N端向下的分子具有更大的旋转激发。由于旋转激励主要是以入射速度的法向分量为代价发生的，这可以很容易地解释实验结果。这是使用经典的轨迹计算确认。因此，NO和Ag（111）之间的相互作用似乎是由各向异性的排斥相互作用，这是更强的O端区域。
Scattering experiments have been performed using orientated beams of NO molecules in the Π½-electronic ground state and J=MJ=½. In direct inelastic scattering we observe that with the O-end of the molecule preferentially orientated towards the surface, the angular distribution shifts away from the specular direction towards the surface. In the experiments on trapping/desorption it appears that trapping is enhanced for the O-end towards the surface. Both results can be interpreted in terms of larger rotational excitation of the molecule with the O-end down than in case of the N-end down. Since the rotational excitation will mainly occur at the expense of the normal component of the incident velocity, this can easily explain the experimental results. This is confirmed using classical trajectory calculations. The interaction between NO and Ag(111) seems therefore to be governed by the anisotropy of the repulsive interaction, which is stronger for the O-end region.