Six-dimensional quantum dynamics of H2 dissociative adsorption on the Pt(211) stepped surface
Six-dimensional quantum dynamics of H2 dissociative adsorption on the Pt(211) stepped surface
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DOI：
10.1063/1.2920488
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发表时间：
2008-05-12
影响因子：
4.4
通讯作者：
Baerends, E. J.
中科院分区：
文献类型：
--
作者：
Olsen, R. A.;McCormack, D. A.;Baerends, E. J.
实验研究的结果，和理论计算利用经典的轨迹，表明，解离的H-2的Pt（211）台阶表面上的增强在低能量的分子捕获机制。由于量子效应可以发挥很大的作用，在低能量和长寿命的分子捕获的特点，我们已经进行了量子动力学计算这个系统，第一个处理所有的分子自由度的气体分子反应在一个阶梯状的金属表面。计算表明，分子捕获在量子系统中持续存在，但仅在比实验观察到的能量低得多的能量下，指出势能面可能存在缺陷。经典和准经典轨道计算在相同的潜力提供了一个合理的反应的整体图片，但许多更精细的细节是不准确的，某些经典的反应机制是完全无效的。我们的结论是，一些怀疑态度，应显示对任何经典的研究，长寿命的陷阱状态发挥作用。(c)2008年美国物理研究所。
Results of experimental studies, and theoretical calculations utilizing classical trajectories, have shown that dissociation of H-2 on the Pt(211) stepped surface is enhanced at low energies by a molecular trapping mechanism. Because quantum effects can play a large role at the low energies and long lifetimes that characterize molecular trapping, we have undertaken quantum dynamics calculations for this system, the first to treat all molecular degrees of freedom of a gas molecule reacting on a stepped metallic surface. The calculations show that molecular trapping persists in the quantum system, but only at much lower energies than experimentally seen, pointing to possible deficiencies in the potential energy surface. Classical and quasiclassical trajectory calculations on the same potential provide a reasonable picture of reaction overall, but many of the finer details are inaccurate, and certain classical reaction mechanisms are entirely invalid. We conclude that some skepticism should be shown toward any classical study for which long-lived trapping states play a role. (c) 2008 American Institute of Physics.