Electron transfer in collisions of dipole-bound anions with polar targets

Charge transfer in collisions between dipole-bound CH3CN− negative ions and the polar target CH3NO2 is examined using a Penning ion trap. A long-lived CH 3 NO 2 - ion signal is observed. It is argued that this results from creation of dipole-bound CH 3 NO 2 - ions that rapidly evolve into longer-lived ions that have predominantly valence-bound character. The charge transfer cross section is sizable, ∼1.4 × 10−12 cm2, but is consistent with a simplified near-resonant charge exchange model.