Dissociation of methanol by ion-impact: Breakup dynamics, bond rearrangement and kinetic energy release

The dissociation dynamics of multiply charged methanol molecules formed in collision with 1.2 MeV Ar8+projectiles is studied. Using coincidence mapping techniques, we can separate out the different dissociation pathways between carbon, oxygen and hydrogen ionic fragments as well as two- and three-body breakup events. Reactions involving intramolecular bond rearrangements within the CH3CH3 group of the dissociative molecule are discussed in detail. A signature of hydrogen migration in doubly charged methanol is observed. Kinetic energy releases of different breakup channels are reported here and compared with values calculated from a Coulomb explosion model. The shape and orientation of the islands in the coincidence map give further information about the momentum balance in the fragmentation process of two- or many-body dissociation pathways.