Investigation of heterodimeric and homodimeric radical cations of the series: [F2O2]+, [F2Cl2]+, [Cl2O2]+, [F4]+, and [Cl4]+

In this state-of-the-art quantum-chemical investigation we report structures, thermochemical stabilities, Born-Fajans-Haber cycles as well as vibrational data of heterodimeric and homodimeric radical cations of the series [F2O2](+), [F2Cl2](+), [Cl2O2](+), [F-4](+), and [Cl-4](+). The so far experimentally unknown species [F-4](+), [F2O2](+) and [F2Cl2](+) are predicted to be thermochemically stable and could be possible targets for gas-phase or matrix-isolation experiments. Furthermore, their stabilities as homodimeric [X-4](+) or heterodimeric [X2Y2](+) radical cation salts in the solid state have been estimated by Born-Fajans-Haber cycles.