AU(2)(2+) has bound excited states

Quasirelativistic Douglas-Kroll CASPT2 calculations are reported for the gr ound and excited electronic states of Au-2(2+). The ground-state potential energy curve is confirmed to be totally repulsive whereas the (3)Sigma(u)() and (1)Sigma(u)(+) excited state curves show metastable minima with barri er heights of 0.66 and 0.37 eV, respectively. Analogous calculations are al so reported for the Au, and Au: ground states. The species, or stares, with one electron in the bonding 6s sigma(8) orbital have almost as short bond lengths as those with two electrons. (C) 2000 Elsevier Science B.V. All rig hts reserved.