The bonding patterns of the [C2O4](2+) dication formed upon interaction of CO22+ with neutral CO2 are investigated using the analysis of domain-averaged Fermi holes (DAFHs). The DAFH approach provides an explanation for the previously observed "asymmetry" of the energy deposition in the pair of CO2+ monocations formed in the thermal reaction CO22+ + CO2 -> [C2O4](2+) -> 2 CO2+, specifically that the CO2+ monocation formed from the dication dissociates far more readily than the CO2+ monocation formed from the neutral molecule.