Medium enhanced, electron stimulated desorption of CF3− from condensed CF3I

It is shown that (a) the cross-section for electron stimulated desorption of CF3− from condensed CF3I is enhanced by more than 2 orders of magnitude with respect to the corresponding gas-phase dissociative electron attachment cross-section and (b) CF3− is ejected from the CF3I film into vacuum with surprisingly high kinetic energy. These observations are explained by a preferential orientation of the molecule at the surface and a particular, medium enhanced, desorption mechanism which is based on the conversion of an open-channel resonance into a closed-channel (Feshbach) resonance when solvated.