Dynamics of the dissociative electron attachment in H₂O and D₂O: the A₁ resonance and axial recoil approximation

Abstract

The dynamics of the formation and decay of negative ion resonance of A₁ symmetry at 8.5 eV electron energy in the dissociative electron attachment (DEA) process in H₂O and D₂O are investigated using the velocity slice imaging technique. While the highest energy hydride ions formed by DEA show angular distributions characteristic to the A₁ symmetry, those formed with low-kinetic energy show considerably different angular distributions indicating changes in the orientation of the dissociating bond due to bending mode vibrations. Our observations are quite different from the recently reported measurements, but consistent with the fully quantum calculations.