The Theoretical Study of the 2D-to-3D Transition and Electronic Properties for Au_n Clusters

The equilibrium structures and electronic properties of Au_n clusters have been studied using density functional theory at the PW91/TZVPP level. The structural optimizations show that the ground state Au_n clusters possess a planar structure for n =3-13 and a solid structure for n=14. The electronic properties of Au_n clusters are analyzed based on the averaged binding energy, second-order energy difference, energy gap, the vertical ionization potential and the electron affinity. It is found that the atomic binding energy of big gold clusters is larger than that of small gold clusters. The even-numbered Au_n clusters are more stable than the odd-numbered ones. The chemical activity of the odd-numbered clusters, which is easy to capture an electron, is higher than the even-numbered ones.