A long-lived triply charged diatomic ion, CS³⁺

A metastable, triply charged, diatomic molecular ion, CS³⁺, has been discovered in collisions of O^- and Si^- with CS₂ at an impact energy of 40-70 keV. Concomitant configuration interaction calculations of potential energy curves and electron density distributions have been carried out which indicate that the lowest-energy ² Sigma _g state of this molecular ion is metastable for at least 3 mu s. Predictions are made of the values of the kinetic energies released upon dissociation of the lowest-energy ^2,4,6 Sigma _g and ^2,4 Pi _g states of CS³⁺.