Possible long-lived quartet resonance states of CO −

Abstract

Two states of CO− which are expected to live longer than the well-known 2Π shape resonance are examined and the results obtained are compared with the analogous states of the isoelectronic N2− system. The 4Σ− and 4Π states are found to be stable with respect to dissociation. The latter state is also stable with respect to single-electron loss to its parent neutral state. The lifetime of this state is supposed to be long, but not necessarily long enough to allow detection in a mass spectrometer.