Structures and electronic properties of AlnVn (n = 2–12) clusters from ab initio calculations

Abstract

The structural and electronic properties of AlnVn (n = 2–12) clusters were studied systematically by using density functional theory. With the lowest-energy structures of AlnVn (n = 2–12) clusters that acquired from ab initio molecular dynamics and optimization calculations, the binding energies, vertical ionization potentials (VIP), vertical electron affinities (VEA), the highest occupied molecular orbital-the lowest unoccupied molecular orbital (HOMO-LUMO) gaps and partial density of states (PDOS) were calculated on GGA-BLYP level. The calculation results indicate that vanadium atoms have a tendency of aggregation in the center of AlnVn cluster, and a much stronger binding energy of V2n clusters than that of AlnVn clusters would be the cause of V atoms aggregate in AlnVn clusters. The PDOS results also show that the binding energy of Al-V bond is much weaker than that of V-V bond due to these two kinds of bonds are bonded in different hybrid ways. This work can not only explain the cause of the poor miscibility between the components of Al-V alloy, but also expound the effect of V on grain refinement in Al-Si alloy.