Production of the molecular dication ArC2+ by ion–molecule reactions

ArC2+ doubly-charged ions have been produced in the reactions of Ar2+ with CO and CO2. These reactions convert an atomic dication into a molecular dication, thus storing energy in a metastable state. For both reactions, we have measured integral cross-sections as a function of collision energy and evaluated reaction energetics. The observation that ArC2+ is produced also at collision energies largely exceeding the value needed for its dissociation suggests that reaction dynamics channels a substantial part of energy in product translation rather than in internal degrees of freedom of ArC2+.