PHOTOCHEMICAL-REACTIONS OF THE RADICAL CATIONS OF FREONS AND TETRAMETHYLUREA IN A FREON MATRIX AT 77 K

The spectral properties of radical cations trapped in an irradiated Fr eon mixture: (CFCl3, CF2BrCF2Br) and solutions of tetramethylurea in t his mixture at 77 K were determined. It was shown that exposure to lig ht in the wavelength range of lambda = 313 to 578 nm resulted in decay of the Freon radical cations. The quantum yields of these processes w ere measured as functions of wavelength. The action of light on tetram ethylurea radical cations was found to result in the formation of Freo n radical cations, in addition to amide-type radicals. The quantum yie lds of photoconversion of tetramethylurea radical cations in various F reon matrices were determined. Photoinduced formation of tetramethylur ea radical cations was found to be due to the action of light on Freon radical cations. The effect of trace amounts of water on the processe s of formation of tetramethylurea radical cations in the Freon mixture was determined.