Structures, stabilities and electronic properties of CunNa (n = 1–8) clusters

The structures, stabilities and electronic properties of CunNa (n = 1–8) clusters have been systematically investigated by using density-functional approach. According to optimized doped clusters, growth behaviors are organized as follows: Na added Cun clusters or Na substituted Cun+1 clusters as well as Cu added Cun−1Na clusters. The calculated averaged binding energies, fragmentation energies, and second-order difference of energies exhibit a pronounced even–odd alternation phenomenon as a function of the cluster size. Electronic properties of doped clusters are studied by calculating the HOMO–LUMO gaps, the contour maps of HOMOS and electrostatic potential. At last, the molecular orbitals, VIP, VEA and chemical hardness are also analyzed.