The Hemibonded Dimer Radical Cation of Thiirane
نویسندگان
چکیده
Ab initio molecular orbital theory has been used to study the formation and reactions of the sulfursulfur hemibonded dimer radical cation of thiirane. Two fragmentation pathways, hemibond cleavage and ethylene extrusion, leading to the fragmentation of this species have been examined. The barriers to these processes are found to be similar and moderately large (127 and 160 kJ mol-', respectively). The results obtained have been used to rationalize the findings of recent gas-phase and Freon-matrix studies of the ion-molecule reactions of thiirane. A recent series of investigations has revealed an intriguing class of ion-molecule reactions involving thiirane (1). In a gas-phase kinetic study,] Baykut, Wanczek, and Hartmann (BWH) examined the rates at which 1 and its radical cation (2) react to form, in the first instance, a sulfonated thiirane radical cation (3) and a molecule of ethylene (4) in what they term a "sulfur-transfer
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