Structures of small YnAlm clusters (n plus m ≤ 6): A DFT study

We conducted DFT studies on the YnAlm binary clusters of size n + m <= 6, to study electronic property variation, using the PBE1PBE method and Lanl2DZ as basis set. The ground-state geometries of yttrium (n >= 4) prefer 3D geometry and Al (m <= 5) desires planar geometry. Yttrium clusters were stabilized by the addition of one or two aluminum atoms. The shape and geometry of the clusters has a profound influence on their band gap and stability. With an increase in the Al composition, segregation was found to occur in the bimetallic systems with the geometry and shape depending on the aluminum composition. The bimetallic clusters have higher electron affinity and stability. (C) 2009 Elsevier B.V. All rights reserved.