Ab initio calculation of the geometries, stabilities, and electronic properties for the bimetallic Be _2Au _n (n=1-9) clusters: Comparison with pure gold clusters

摘要

Ab initio methods based on density functional theory at BP86 level were applied to the study of the geometrical structures, relative stabilities, and electronic properties of small bimetallic Be _2Au _n (n=1-9) clusters. The optimized geometries reveal that the most stable isomers have 3D structures at n=3, 5, 7, 8, and 9. Here, the relative stabilities were investigated in terms of the averaged atomic binding energies, fragmentation energies and second-order difference of energies. The results show that the planar Be _2Au _4 structure is the most stable structure for Be _2Au _n clusters. The HOMO-LUMO gap, vertical ionization potential, vertical electron affinity and chemical hardness exhibit a pronounced even-odd alternating phenomenon. In addition, charge transfer and natural electron configuration were analyzed and compared.