Journal or Book Title
Journal of Chemical Physics
Ab initio quantum chemical methods are applied to the study of ethylene decomposition to acetylene and molecular hydrogen in the ground electronic state. Results are reported on three different pathways for ethylene decomposition—two stepwise processes involving a hydrogen transfer followed by 1,1 elimination of H2, or vice versa, and a 1,2 elimination. The latter proceeds through an energy maximum with two imaginary frequencies, rather than one as for conventional transition states. Ethylidene and vinylidene are predicted to be stationary points on the C2H4 and C2H2potential energy surfaces, respectively. Recent photochemical studies have observed rotationally hot H2. It is shown that due to the excess energy available in the photochemical experiments, all three mechanisms can give rise to rotationally hot H2 when proper account is taken of the transverse vibrational modes along the reaction paths.
Copyright 1994 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
American Institute of Physics
Jensen, Jan H.; Morokuma, Keiji; and Gordon, Mark S., "Pathways for H2 Elimination from Ethylene: A Theoretical Study" (1994). Chemistry Publications. 242.