Density Functional Theory investigation for Sodium atom on Copper Clusters

Density functional theory has been performed for NaCun clusters, (n=4, 5, 6, 7). Optimization plus frequency at the ground state level, B3LYP, 3-21G basis sets has been investigated. The charges for all clusters are equal to zero (neutral charges). Molecular orbital theory has been used to find HOMO and LUMO energies. Total energy, dipole moment have been computed. Koopman's theorm has been used to calculate the ionization potential and electron affinity. Also the electronegativity has been evaluated for sodium atom, pure copper clusters and NaCun clusters. Surfaces (HOMOand LUMO) and contours (electrostatic potential) have been carried out. All calculations have been investigated by using Gaussian 09 software package.