Orientation and alignment effects in ion-induced fragmentation of water

The angular distribution of recoil ion fragments in ion-impact dissociation of small molecules has been a subject of several theoretical and experimental investigations. Most of the studies reported on this subject have been conducted with diatomic molecules as target species. Such studies are needed to address the role of post-collision interaction in ion-molecule interaction and to get information about alignment dependent cross sections for electron removal from molecules. Both these two effects are strongly correlated to the ion-molecule interaction time and hence to the velocity of the projectile. We have performed an experiment with a simple triatomic molecule, D₂O to study the angular distribution of fragment ions with respect to the direction of incoming ion beam