ИСТИНА

Nowadays the advisability of using of irradiation is an actual question for chemical indus-try. In view of the aforesaid investigations of the activity of organic species in the irradiat-ed systems were carried out. This report represents us the results of studies of some bifunctional radical cations with so called methylene “bridge”: Y–С(О)–Хn– С(О)– СН3 , где n = 0, 1, 2 Х = –СН2– Y = CH3– n = 1, X = –CH(CH3)– Y = CH3– n = 0 Y = C2H5– The irradiation process was studied by the example of diketones radical cations in freon matrices. The experimental data includes EPR and UV spectra. The radical cations were generated by irradiation of the frozen samples at 77 K. To avoid the objectionable photo chemical reactions between the solute species all the works were being done in the dark-ness. After the samples were irradiated with X-rays and the first spectra were obtained the irradiation with several wave-length range light came and the spectra were measured again. This procedure was repeated several times and some of the most stable samples were heat-ed to the temperature near 130 K and then the spectra were measured again. In general case most of spectra obtained show us anisotropy of g-factor. Comparing the experimental data one can make a conclusion that most of spin density is possessing by two carbonyl groups. The unpaired electron in these radical cations is concentrated on the two functional groups what is confermed by the EPR spectra. The nuclear fields of hydrogen belonging to the extremes methylene groups don’t almost affect the spectum patterns but the “bridge” protons do. It’s clear that the hyperfine splitting showed on the spectra depends on the length and the structure of the very “bridge”. The spectra of diacetyl and 2,3-pentandion don’t show the hyperfine splitting at all except of after being heated. They represent us the unsolved singlets. Moreover it must be mentioned that the diketon radical cations obtained are rather resistent to the light with a wide range of wave-length. The heating to the temperature near 130 K don’t affect their shape too but the lines which become more broad. Furthermore two various marks of freon were used like solvents in this work to study the effect of the environment on the radical cation properties.