Dirac scattered-wave calculations for Ag2+3, Auq+3, and Auq+4 (q=1, 2) clusters

Dirac scattered-wave (DSW) calculations are presented for the Ag2+3, Au+3, Au2+3, Au+4, and Au2+4 clusters. The results show that relativistic effects in bonding are not negligible for the silver cluster; whereas for the gold clusters these are very significant and lead to appreciable s–d hybridization in the bonding molecular orbitals. Zeeman and hyperfine tensors have been calculated for the Ag2+3, which are in very good agreement with the experimental results. These tensors are also predicted for the Au2+3 cluster. First ionization potentials and excitation energies are predicted for all these cationic clusters using the spin-restricted transition state method. Contour diagrams which clearly reveal the significant relativistic effects in bonding are also presented.