Thermal energy ion condensation reactions in benzene vapor

A pulsed electron beam coupled to a time-of-flight mass spectrometer has been used to study bimolecular reactions of C6Hx+ ions with the benzene molecule. Rate constants for formation of the complexes C12H10+, C12H11+, and C12H12+ have been obtained for electron impact energies of 20, 30, and 50 eV. Rate constants of several reactions involved in the decay of the C12H10+ and C12H11+ complexes have also been obtained. A measurement of the lifetime against decay of the C12H11+ complex yielded an upper limit of 150±50 μsec for an electron impact energy of 40 eV.