Approximation of the interaction of oxygen and nitrogen with Pd and Ni surfaces using the Morse potential

Abstract

The interaction potential of an atom–metal surface system was constructed by the 5-parameter Morse potential (5-MP) method. The adsorption and diffusion dynamics of oxygen and nitrogen atoms on flat and stepped Pd and Ni single-crystal surface systems were selected to validate the 5-MP method. The calculated data of adsorption sites, adsorption geometry, binding energy, eigenvibration and the diffusion process are in relatively good agreement with the experimental results and explain well some of the controversies of experimental analysis. This shows that our theoretical model is feasible for simulation of the interaction between adatoms and metal surfaces, and may accurately reflect the condition of materials surface modification in nature. Moreover, the role of the step defect for adatoms is also discussed related to the cases on the flat surface. The theoretical analysis may provide useful information for experimentalists to design appropriately surface modification, chemical vapor deposition and catalysis reaction processes.