Theoretical Study Of Adsorption, Diffusion On Gas-state Surfaces

The interaction between atoms, molecules and metallic surfaces is an importantresearch topic in the field of heterogeneous catalysis, gas erosion and crystal growth. Thedynamics of gas-surface interacting is awaking more and more interest in the community ofphysicists and chemists during the past decades. And the surface adsorption as the key ofcatalysis between different phases has taken on the more and more expansive prospect .Therefore, the study on the interaction beween atom, molecule and catalyzer surface,especially the interaction with active sites by theory is necessary. The main contents of thiswork are as follows:It describes the meaning of study, the experimental and theoretical methods instudying the adsorption. 5-Morse potential method and improved extended LEPSpotential method were introduced in detail in chapter 1.The S-Ni, S-Cu and S-Rh, O-Al, H-W interaction systems entirely investigated byconstructing atom-surface interaction potential named five parameters Morse potential(5-MP for short) in chapter 2.The analytical potential of gaseous diatom molecule interaction system, i.e. LEPSpotential has been constructed. And the CO-Ru systems are studied in chapter 3.The main research fruit in this work is as follows:1. The adsorption system of S atom on the Ni metal surface. The adsorption and diffusion ofS-Ni system are investigated with 5-MP method that we advanced in detail,which make itpossible for people to understand this key system detailedly and completely. On the three lowindex surfaces, S atom is located at high cooperated site. S atom is located at the fourfoldhollow site on the Ni(100) surface, and at the threefold hollow site on the Ni(111) surface. Onthe Ni(110) surface, S atom is located at fourfold hollow site. The adsorption of S atom onNi(311) step surface was researched in this article, the calculated results show: S atom islocated at the fourfold hollow site and hcp threefold hollow site, while the fcc threefoldhollow is annihilated during completing with the fourfold hollow site.