Knowledge Bank

Potential curves for the ground and low-lying excited states of AuF have been calculated using spin-orbit configuration interaction. Relativistic effective core potentials were employed. The ground state was found to be a closed-shell, ionic state that eventually separates into open-shell neutral atoms. The excited states show more unusual behaviour. Even at $Re$, some of the excited states show extensive spin-orbit mixing. The ground state is bound, but several of the excited states are metastable at best. For example, eight states, including the ground state, have an asymptotic limit of Au $5d^{10}$6s F $2p5$. Only three of these states are bound. In each of three other states, there is a potential maximum that might allow a few bound vibrational levels. In contrast, all eight of the comparable states of CuF are bound.