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Updated: Mar 16, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Matrix-isolation and computational study of H2CCCl and H2CCBr radicals
Cheng Zhu1, Luís Duarte1, Leonid Khriachtchev1
1Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland.
Abstract:
We report on two new radicals, H2CCCl and H2CCBr, prepared in low-temperature noble-gas matrices and characterized using infrared spectroscopy. These radicals are made by UV photolysis of HCCCl and HCCBr and subsequent thermal annealing to mobilize hydrogen atoms in the matrices and promote their reaction with the residual precursor molecules. Three characteristic infrared bands are observed for each radical. The assignments are supported by quantum chemical calculations at the B3LYP and CCSD(T) levels of theory with the def2-TZVPPD basis set.
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