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Spectral characteristics of the radical cations (RC) of DMF (~max = 415 nm, em~ x = (2.6+0.8)" 103 L mol -I cm -1) stabilized in an irradiated glassy freon mixture (CFC13 and CF2BrCF2Br) at 77 K were determined. Amide type radicals and RC of the matrix were shown to be formed by irradiation (~. = 365--436 nm) of the radical cations of DMF in freon matrices using ESR and UV spectroscopy. The quantum yields of photoconversion of the DMF radical cations are independent of the wavelength of exciting light. It was found that the matrix structure affects the processes stabilizing the products of photoconversion of the DMF radical cations.Radical cations (RC) are active intermediates formed in various radiochemi.cal, photochemical, catalytic, etc.

Radical products of radiolysis of frozen solutions of propionic and butyric acids were studied in the matrices of Freon-11, Freon-113, and Freon-113a at 77 K. It was shown that the primary radical cations generated by radiation were not trapped in the freonic matrices (in contrast with the corresponding freonic solutions of acetic acid). The radical cations of propionic and butyric acids decay in concurrent processes of rearrangements yielding terminal-type and ylide-type distonic radical cations and intramolecular proton transfer in the dimeric radical cations resulting in acyloxy radicals. The latter species undergo decarboxylation to yield ethyl and propyl radicals for propionic and butyric acids, respectively. According to mass-spectrometric data, the terminal-type distonic radical cations undergo the McLafferty rearrangement.

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