Doublet and quartet states of Li-2(-)

Electronic states of the molecular lithium anion are investigated by config uration-interaction calculations. Comparison with the analogously computed potential energy curves for the lowest singlet and triplet states of the ne utral Li-2 shows that in addition to the well-known stable ground state X(2 )Sigma(u)(+) there also exist metastable excited states of Li-2(-). Within the quartet sector, two candidates for such long-lived states are identifie d and their spectroscopic properties studied.