Structure and electronic properties of copper clusters. An Ab Initio LCAO–MO–SCF Study

Abstract

The structure and electronic properties of copper clusters Cu_n(n= 2-5, 8 and 13) have been studied through ab initio LCAO–MO–SCF calculations with a Gaussian basis set (12, 7, 5) contracted to [5, 3, 2]. The linear structure is more stable than the two- and three-dimensional structures for n= 3 and 4, but becomes less stable for n 5. Since for Cu₈ the band of 3d levels and the 4s levels are well separated and for Cu₁₃ the two bands just begin to overlap, the distribution of energy levels in these clusters appears to be rather different from that in the bulk metal. This is also a consequence of the fact that most of the atoms in the cluster Cu₁₃ are surface atoms. The binding energy increases quasi-linearly with the number of atoms in the cluster up to n= 8.