FTIR spectroscopic study of 1,1,1-trifluoro-2-chloroethyl and 1,1,1-trifluoro-2-chloroethylperoxyl radicals

A combination of matrix isolation and FTIR spectroscopy was applied to inve stigate 1,1,1-trifluoro-2-chloroethyl (1) and 1,1,1-trifluoro-2-chloroethyl peroxyl (2) radicals. Radical 2 was obtained by vacuum pyrolysis of 1,1,1-t rifluoro-2-bromo-2-chloroethane (3). Corresponding peroxyl radicals was gen erated by co-condensation of pyrolysis products and molecular oxygen in an argon matrix. To assign the experimental bands DFT calculations (B3LYP/6-31 1G**) were carried out. The fundamental bands of O-O and C-O stretching vib rations of peroxyl radical CF3CHClOO (1102.1, 972.7, cm(-1)) were identifie d by their red shifts to 1044.7 and 954.1 cm(-1) in the spectra of O-18 sub stituted derivatives. UV photolysis of the radical 2 in the low-temperature matrix produced difluoroformaldehyde CF2O, radicals ClCO, CF3, as well as CO and HCl as the primary photoproducts. (C) 1999 Elsevier Science B.V. All rights reserved.