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The dynamics and kinetics of alkane adsorption on platinum(111), palladium(111), and nickel(111).

机译：烷烃在铂（111），钯（111）和镍（111）上吸附的动力学和动力学。

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An understanding of molecular adsorption processes on metal surfaces is important to heterogeneous catalysis, since in most cases reactants must first adsorbe on a surface before they react. Due to the importance of transition metals as a catalyst for reactions, the adsorption of reactants has attracted much attention both experimentally and theoretically. Generally speaking, the success of a model can be classified as qualitative, quantitative, or predictive. Surely predictive models are most significant because they provide insights into other systems through quantitative postulation. In this dissertation, the dynamics and kinetics of adsorption of gas phase adsorption on transitional metals is analyzed and molecular dynamics simulations are utilized to predict the probabilities of adsorption of small molecules on metal surfaces over a wide range of incident kinetic energies and angles.; The dynamics of molecular adsorption of small alkanes, carbon dioxide, and rare gases on Pd(111), and Ni(111) was studied by supersonic molecular beam technology and stochastic trajectory simulations and comparisons with Pt(111) were made. The simulations utilizing the methyl(methylene)-Pt Morse potential obtained from alkane trapping on Pt(111) predict that the trapping probability of alkanes at a given incident kinetic energy and angle should be largest for Pd(111) and smallest for Ni(111), with Pt(111) lying in between. Whereas the mass difference accounts for the difference between the trapping probabilities on Pt and Pd, the greater lattice stiffness of Ni leads to a significant lowering of the trapping probability. Experimentally we do observe that the adsorption probability increases in order of Ni(111) to Pt(111) to Pd(111) for alkanes and rare gases. Besides, the simulations accurately predict the corresponding experimental values of the initial trapping probability of alkanes trapping on Pd(111), and the predictions of the trapping of the alkanes on Ni(111) is within a factor of two, at worst, over the range of incident energies studied. More accurate agreement for Ni(111) was obtained by adjusting the Morse potential parameters. The molecular dynamics was also employed to predict CO2 adsorption on Pd(111) using a set of Morse potential obtained from CO 2 trapping on Pt(111), and reasonable agreement with the experimental results was obtained.
机译：了解金属表面上的分子吸附过程对于非均相催化很重要，因为在大多数情况下，反应物必须先吸附在表面上才能进行反应。由于过渡金属作为反应催化剂的重要性，因此反应物的吸附在实验和理论上都引起了人们的广泛关注。一般而言，模型的成功可分为定性，定量或预测性。当然，预测模型最重要，因为它们可以通过定量假设提供对其他系统的见解。本文对过渡金属上气相吸附的动力学和动力学进行了分析，并利用分子动力学模拟预测了小分子在大范围的入射动能和角度下在金属表面的吸附概率。利用超声分子束技术研究了小链烷烃，二氧化碳和稀有气体在Pd（111）和Ni（111）上的分子吸附动力学，并进行了随机轨迹模拟，并与Pt（111）进行了比较。利用在 Pt （111）上烷烃捕集获得的甲基（亚甲基）-Pt摩尔斯电势进行的模拟预测在给定的入射动能和角度下，烷烃的捕集概率对于Pd（111）应该最大，对于Ni（111）应该最小，而Pt（111）介于两者之间。质量差解释了Pt和Pd上的俘获概率之间的差异，而Ni的较大晶格刚度会导致大大降低俘获概率。从实验上我们确实观察到对于烷烃和稀有气体，吸附概率按Ni（111）至Pt（111）至Pd（111）的顺序增加。此外，模拟准确地预测烷烃在Pd（111）上的初始俘获概率的相应实验值，并且烷烃在Ni（111）上的俘获的预测在一个因子之内。在最坏的情况下，有两个在研究的入射能量范围内。通过调整摩尔斯电势参数，可以获得更准确的Ni（111）一致性。分子动力学还被用来预测CO 2 在Pd（111）上的吸附，这是利用从Pt（111）上俘获的CO 2 所获得的一组摩尔斯电势进行的，并且合理获得了实验结果。

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