Excited states of gaseous ions. Transitions to and predissociation of the C2Σ+ u state of N2+

A configuration interaction study of different electronic states of N+ 2 has been performed. The position in energy and the relative intensity of the photoelectron bands of the 2Σ+ u states has been calculated and compared with experiment. The C2Σ+ u state is predissociated by a 4Πu state, as previously supposed. However, owing to the attractive nature of the 4Πu state a double crossing occurs. Several predissociation mechanisms of the C state can therefore take place; their lifetimes have been calculated. © 1972.