Bent dissociative states of CO22+

The geometry of the excited states of dicationic CO2 undergoing a three-body break-up has been estimated by momentum imaging of fragment ions. The momentum of the neutral fragment has been deduced from the momentum balance in the break-up. Our analysis shows that CO22+ has two electronic states with bent geometries which lead to three-body break-ups. We further propose that one of the dissociation channels follows from a bent symmetric stretch and the other from a bent asymmetric stretch. Analysis of the kinetic energy of the ions and of the momentum of the neutral fragment favours the proposition.