A MO Studies of Dissociative Chemisorptions of Some Diatomic Molecules on （111） Surface of Ni and Its Alloys

The extended Huckel molecular orbital method was used to examine the interactions of first row diatomic molecules （Li₂, B₂, C₂, N₂, CO, NO, O₂and F₂） with eight atom clusters representing （111） crystal surfaces of Ni and its alloys （Ni₃Mn₅, Ni₃Cu₅）. Based on our calculation results, we could make the following predictions: （1） From Li₂ to F₂, the adsorption energy Ea decreases, and these three catalysts (Ni₈, Ni₃Mn₅, Ni₃Cu₅) are suitable for dissociative chemsorption of C₂, N₂, CO and NO; （2） The promoter, Mn or Cu, in Ni alloys decreases the chemsorption energy Ea, and affects some properties of the diatomic molecules. These predictions are in agreement with experimental facts when available, and they have been explained on the basis of the electronic structure, bonding nature and adsorbed positions.