Electron detachment via direct coupling and charge exchange to shape resonances in negative-ion-molecule collisions

Abstract

Results of a differential time-of-flight energy-loss study of negative-ion (H-, F-, Cl-) and molecule (N2, CO, D2) collisions are reported. It is found that in addition to a continuous distribution, which can be attributed to a direct detachment process, the neutral H atoms energy-loss spectra display prominent peaks at the position of the N2-2 Pi g and CO-2 Pi resonance. These results indicate the major importance of charge exchange to shape resonances in H--molecule collisions. In the case of F- and Cl- ions, no peaks were observed at the position of the N2- resonance and hence our results do not indicate that charge exchange is important in collisions of F- and Cl- with N2.