State-specific low temperature reactions (HBr+, DBr+) [2Πi,v] + (H2, D2): channels and rates

The channels of the HBr+(Πi,v) + D2 and DBr+(Πi,v) + H2 ion–molecule reactions were investigated in a state-selective manner at low temperatures in a free jet. The selected spin–orbit and vibrational states of the ions were prepared by resonance-enhanced multiphoton ionisation. All three energetically accessible channels of the reactions were under consideration using time-of-flight mass spectrometry. The dependence of the rate coefficient of the atom transfer channel versus reaction energy appears to be common to all ion–molecule pairs studied here and previously: HBr+ + H2, HBr+ + D2, DBr+ + H2, DBr+ + D2.