Adsorptions of atoms, molecules and free radicals on Ni(100) surface: A first-principles study

In the present paper, the adsorption of some atoms (H, O, N, S and C), molecules (N₂, CO, NO and NH₃), and free radicals (CH, CH₂, CH₃, CN and OH) on Ni(100) surface were systematically investigated via first-principles density functional theory (DFT) and periodic slab model. The adsorption structures were optimized, and the preferred adsorption site, adsorption energy, and diffusion energy barrier were obtained. The order of adsorption energy is N₂ < NH₃ < CO < CH₃ < NO< H < OH 2 < CN < S < O < N 2, which prefers the top site; the free radicals CH₂, CH, OH and CN prefer the hollow site, whereas CH₃ tends to be adsorbed on the bridge site. (authors)