The ionization potentials of Ag n and Au n and binding energies of Ag n, Au n, Ag n+ and Au n+ ( n = 1–4)

Abstract

The ionization potentials and binding energies of gold and silver clusters and their positive ions containing up to four atoms are investigated using a complete active space MCSCF followed by multi-reference singles + doubles CI which included up to 1.9 million configurations. The ionization potentials for both Au n and Ag n as a function of cluster size n exhibit an interesting “saw-tooth” behavior. The total binding energies of both the clusters and ions as a function of size reveal that the tetramers of gold and silver exhibit unusual stabilities. The gold clusters in general have larger AEs and IPs in comparison to silver clusters due to relativistic effects.