DFT study of electronic structure and geometry of neutral and anionic silver clusters

Abstract

A comparative analysis of bond lengths ( r e), vertical detachment energies (VDE), excitation energies of neutral clusters with geometry of anions ( T e) and vertical ionization potentials of neutral clusters ( IP v) calculated within density functional theory (DFT) using different functionals with both effective core potential (ECP) and all-electron basis sets for silver clusters Ag n , n≤6, have been carried out. DFT methods provide a good agreement between calculated and experimental data of some characteristics. The accurate prediction of all characteristics simultaneously can be achieved with all-electron DZVP basis set only. A new functional has been developed. It provides results close to experimental data using the moderate basis set. For anionic clusters Ag 2–10 −, the difference between calculations with this functional and experimental values of VDE and T e for the most stable isomers does not exceed 0.1 eV. Based on both total energy calculations and comparison of experimental and calculated photoelectron spectra, the structural assignment of clusters Ag 7 −, Ag 9 − and Ag 10 − has been made. The electronic structure and geometrical characteristics of the low-lying isomers has been studied.