Conformation of radicals in a γ- irradiated linear perfluoroalkane at 77 K
Tóm tắt
The principal geometrical parameters of the carbon skeleton of ~CF2CFCF2~ and ~CF2CF2 radicals at 77 K show good agreement with spiral configuration of a perfluoroalkane molecule in crystal. The conformations of radicals resulting from fluorine atom abstraction or C-C bond cleavage are determined by minimum of bond rotation potential energy in a linear perfluoroalkane helix. The analysis of the spectrum of ~CF2CFCF2~ and ~CF2CF2 radicals formed in γ-irradiated linear n-perfluorododecane and polytetrafluoroethylene was performed. The conformational angles and hyperfine coupling constants were determined for α- and Β-fluorine atoms at 77 K.
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