Structure and electronic properties of BenNa(n=2-14) cluster from density-functional theory

The lowest-energy structures and electronic properties of BenNa(n= 2-14) clusters were studied by using density-functional theory (DFT) at B3LYP/6-311G (d) level. The equilibrium geometries of BenNa clusters with size up to n=14 were determined from a number of possible structural isomers at each size. Our results indicate that Na prefers to be on the periphery of Be clusters. Both Be4Na and Be9Na clusters were found to be particularly stable with higher binding energy and larger electronic gap. For all the BenNa clusters studied, we found charge transfers from Na to Be site and co-existence of covalent and metallic bonding characteristics. (authors)