A Vacuum Ultraviolet Photoionization Mass Spectrometric Study of Ethylene Oxide in the Photon Energy Region of 10−40 eV

The photoionization and dissociative photoionizations of ethylene oxide have been studied both experimentally and theoretically. In experiments, photoionization efficiency spectra for ions C 2 H 4 O +, C 2 H 3 O +, C 2 H 2 O +, C 2 HO +, CH 3 O +, CH 2 O +, CHO +, C 2 H 4 +, C 2 H 3 +, C 2 H 2 +, C 2 H +, CH 4 +, CH 3 +, CH 2 +, CH +, and C + have been obtained. In addition, the energetics of the dissociative photoionizations have been examined by ab initio Gaussian-2 calculations. The computational results are useful in establishing the dissociation channels near the ionization thresholds. The dissociation channels established may be broadly divided into two types: simple bond cleavage reactions and those involving transition structures and activation energies.