Three-body fragmentation of CO22+upon K-shell photoionization

The fragmentation dynamics of CO2 molecules subsequent to K-shell photoexcitation and ionization was studied using a multicoincidence ion momentum imaging technique. The detailed analysis via fragment momentum correlation plots (Newton diagrams) clearly reveals concurrent fragmentation mechanisms for the three-body dissociation of CO(2)2+ into C++O++O, for both linear and bent geometry states of CO(2)2+. The experimental results are supported by a classical trajectory simulation based on a Coulomb explosion model, which elucidates energy and angular correlations between fragments for different fragmentation processes.