Geometries, stabilities and electronic properties of bimetallic AlnPdm (n = 1–10, m = 1,2) clusters

Abstract

The geometries, stabilities and electronic properties of Al[Formula: see text]Pd[Formula: see text] (n = 1–10, m = 1, 2) have been systematically investigated by using the DFT method at B3PW91/GENECP level. The optimized results indicate that the lowest-energy structures of Al[Formula: see text]Pd clusters prefer to form three-dimensional (3D) structures and the Pd atom occupies a peripheral position of Al[Formula: see text]Pd clusters. The most stable Al[Formula: see text]Pd2 clusters can be obtained by adding one Al atom to the most stable structure of Al[Formula: see text]Pd2 clusters except for n = 7 and 10. The two Pd atoms are found to occupy the exclusive surface sites. The analysis of stabilities reveals that Al3Pd[Formula: see text] and Al7Pd[Formula: see text] clusters are more stable than their neighbors. The doping of Pd atoms enhances the stabilities of aluminum clusters. The charges always transfer from Al atoms to Pd atoms in Al[Formula: see text]Pd[Formula: see text] clusters. There exists strong spd orbital hybridization between Pd and Al. The results of polarizability imply that the nucleus and electron cloud of these clusters are easily affected by the external field and the nonlinear optical effect of Al[Formula: see text]Pd and Al[Formula: see text]Pd2 clusters is enhanced with the increase of cluster size.