Ab initio study of small AunPd2 (n=1-4) clusters

Palladium-doped gold clusters, AunPd2 (n=1-4), were investigated by two Pd-atom substitutions on the Aun clusters using the density functional method Becke3LYP with relativistic effective core potentials (RECP) and LANL2DZ basis set. The possible stable geometrical configurations with their electronic states are determined, and the stability trend of Pd-doped Aun clusters are compared to that of pure Aun clusters. Our results show that the gold-palladium interaction is strong enough to modify the known growth pattern of bare gold clusters, and indicate that the larger the Aun cluster is, smaller the distortions by the two Pd-atom substitutions are. The present calculations are useful to understand the enhanced catalytic activity and selectivity gained by using palladium-doped gold catalyst.