The Theoretical Study of O2 Adsorption on NiTi (100) and (110) Surfaces

The discrete variational Xα method (DV-Xα) within the framework of density-functional theory was applied to study O 2 molecule adsorption on NiTi (100) and (110) surfaces.The bond order and charge distribution between Ti and O atoms for two possible O 2 molecule adsorption ways on NiTi(100) and (110) surfaces were calculated.It is found that the adsorption way for O-O bond perpendicular to NiTi surface is preferred to that for O-O bond parallel to NiTi surface,and O 2 molecule only interacted with one nearest surface titanium atom during the adsorption process.Mulliken population and the partial density of state analysis show that the interaction between Ti and O atoms is mainly donated by O 2p and Ti 4s electrons on NiTi(110) surface,O 2p and Ti 4s,4p electrons on NiTi(100) surface,respectively.The total density of state analysis shows that NiTi(100) surface is more favorable for O 2 molecule adsorption.