The channels of the HBr+(Pi(i), v) + D-2 and DBr+(Pi(i), v) + H-2 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+ + H-2, HBr+ + D-2, DBr+ + H-2, DBr+ + D-2. (C) 2004 Elsevier B.V. All rights reserved.