The O <sub> 2 </ Sub> </ Sub> On Pt <sub> M Of Pd <sub> N </ Sub> (m + N <= 5) Clusters, Chemical Adsorption, Decomposition Of The Theoretical Research,

The density functional theory B3LYP method is used in the geometry optimization and frequency calculation in this paper. For oxygen, the polarized basis set 6-31lg* was used. For the Pt and Pd atoms, we used the Los Alamos National Laboratory's (LANL) basis set with effective core potentials (ECP) of double-ζ type. At first, we optimized the geometries of Pt_mPd_n (m+n<=5) clusters, then we chose the most stable clusters as the sorbent to stimulate the course of the chemisorption of O₂ from which we can compare the extent that the O₂ was activated according to the bond length of O-O and the frequency of O₂. The conclusion is made that alloy cluster Pt-Pd can activate O₂ better than Pt and Pd clusters. At the meantime, O₂ that adsorbed with the Yeager model at the side of Pt-Pt modified by Pd is activated most.In Pt-Pd clusters, the electronic configuration of the Pt was modified owing to the addition of the Pd atom and its number of electrons in the orbital of d are more than those in pure Pt clusters. Because of the effect of the Pd, the empty proportion of d orbital is increased which brings about the strong interaction of metallic atoms and O₂. From the Mulliken charge we can conclude that the electrons flow mainly from the metallic atoms to the π * orbital of the adsorbate (O₂) which will bring the dissociation of the O-O.