The Infrared Spectra of C2H4+ and C2H3 Trapped in Solid Neon
Marilyn E. Jacox, Warren E. Thompson
When a mixture of ethylene in a large excess of neon is codeposited at 4.3 K with a beam of neon atoms that have been excited in a microwave discharge, two groups of product absorptions appear in the infrared spectrum of the deposit. Similar studies using C2H4-1-13C and C2D4 aid in product identification. The first group of absorptions arises from a cation product which possesses two identical carbon atoms, giving the first infrared identification of two fundamentals of C2H4+ and three of C2D4+, as well as a tentative identification of v9 of C2H4+. The positions of these absorptions are consistent with the results of density functional calculations and of earlier photoelectron studies. All of the members of the second group of product absorptions possess two inequivalent carbon atoms. They are assigned to the vinyl radical, C2H3, and to C2D3, in agreement with other recent infrared assignments for those species.