Potential energy curves for the triplet states of the ionic excimer Ar2 2+ are computed in an all-electron treatment employing multireference configuration interaction (MRD-CI) calculations. The six states 3Σ+ u (2), 3Πg, 3Πu, 3Δu and 3Σ- g dissociating into Ar+(2Pu) + Ar+(2Pu) are confirmed to be repulsive, while the four triplets 3Πg, 3Πu, 3Σ- g and 3Σ- u dissociating into Ar2+ (3Pg) + Ar(1Sg) are computed to be weakly bound possessing equilibrium distances between 5·6 and 6·0 bohr and dissociation energies in the range of 2450–3180 cm-1. According to the calculation, the strongest bound-free emission occurs from v′ = 0 of the 23Πg state at 182 nm followed by the 23Πu -3Πg transition at 181·8 nm and de-excitation from the 3Σ- u state around 168 nm; it is unambiguously assigned to the first maximum measured around 183 nm in the third continuum of the argon excimer spectrum. The calculated radiative lifetime of 6 ns (compared with the measured value of 5 ns) also supports this assignment.