THE ENERGETICS OF RESONANT DISSOCIATIVE ELECTRON-ATTACHMENT TO MOLECULES OF 5-MEMBERED HETEROCYCLIC-COMPOUNDS

The thermochemistry of resonant dissociative electron attachment proce sses for furan, thiophene, selenophene, and pyrrole molecules has been studied. The structures of the dissociation products originating from negative molecular ions at energies ranging from 2 to 6 eV have been established using the measured appearance energies of fragment ions an d the known thermodynamic functions of radical and molecular dissociat ion products. Heats of formation and electron affinities for some radi cals and molecules have been assessed by calculations and estimated ex perimentally. It has been concluded that the majority of the fragment ions are formed via rearrangement processes in molecular or fragment i ons.