Optical-optical double resonance spectroscopy is used to obtain total rate constants, electronic branching ratios, and vibrational product state distributions for non-adiabatic transitions among the first-tier ion-pair states of the I-2 molecule excited to the E-g(0+), v(E) 8, 13, 19;J(E) approximate to 55 rovibronic levels in collisions with M = CD3I and CH3COCH3. It is shown that I-2(E ->(M) D) near-resonant transitions are caused by the interaction between the transition dipole moment of I-2(E-D) and the permanent electric dipole moment of M. The I-2(D) state vibrational levels populated due to polarization interaction accompanied by quasi-resonance excitation of the collision partner are also observed. (C) 2008 Elsevier B.V. All rights reserved.