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Updated: Jul 7, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
The nu1 CH stretching mode of the ketenyl (HCCO) radical
Michael J Wilhelm1, William McNavage, Raymond Groller
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Abstract:
The nu(1) CH stretch, a previously uncharacterized mode of the ketenyl (HCCO) radical, has been identified at 3232 cm(-1) through time-resolved Fourier transform infrared emission spectroscopy of rovibrationally excited ketenyl generated, along with ethyl (CH(2)CH(3)), with near-unit quantum efficiency via the 193 nm photodissociation of ethyl ethynyl ether. IR emission from the vibrationally excited photoproducts was detected with both temporal and frequency resolutions. Spectral assignments were supported by comparison with theoretical calculations as well as two-dimensional correlation analysis.
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