Decomposition of propionyl chloride triggered by slow electrons

Low energy electron attachment to propionyl chloride is studied by means of a crossed beam experiment. Two distinct resonances are observed located near 0 and 0.7 eV. The first resonance is attributed to a temporary occupation of the lowest unoccupied molecular orbital (LUMO) with predominant π CO ∗ character. It mainly decays into Cl−, but also the fragments (M–CH2)−, COCl− and (M–Cl)− are observed. In addition the non-decomposed parent molecular anion M− is observed. The second resonance exclusively leads to Cl− formation. It is characterized as temporary occupation of a repulsive σ C – Cl ∗ MO.