State-selective, energy-and angle-resolved collisional interactions of CF22+ dications with atomic and molecular gases are studied at low collision energies. Single-electron transfer measurements help resolve the prevailing ambiguity vis-a-vis the lowest ionization energy of CF2+, yielding a value of 20.55 +/- 0.5 eV. Ground state ((1)Sigma(g)(+)) CF22+ captures an electron from Ar, D-2, N-2 and CF4 predominantly into the ground 6a(1) orbital of CF2+ but in CF22+-O-2 and H2O collisions, the dominant capture channel is the excited (4b(2)) orbital of CF2+. Data are qualitatively interpreted using 'reaction windows' calculated using the Landau-Zener and extended over the-barrier Models. (c) 2005 Elsevier B.V. All rights reserved.