Radiolysis of alcohols at low temperatures. Part 4.—Spectrophotometric investigation of trapped electrons and other species formed by gamma-irradiation in glassy normal alcohols C2—C6

Abstract

The absorption spectra of trapped electrons in irradiated glassy normal alcohols from ethanol to hexanol have maxima in a narrow interval of wavenumbers from 1.85 × 10⁶ to 1.73 × 10⁶ m^–1 but they differ considerably in their width which increases with the increasing length of the alkyl group. The apparent extinction coefficient and oscillator strength decrease linearily with the increasing number of carbon atoms in alcohol. The analysis of the kinetics of photobleaching of trapped electrons, and of the changes of parameters of their absorption spectra caused by light and/or heating, indicate the existence of several kinds of trapped electrons, the composition of which changes during the bleaching process. The total spectrum is an envelope of the partial spectra and it is suggested that it corresponds to excitations of electrons to different levels. Also in the u.-v. region some weak absorption maxima belonging to trapped electrons might exist. A broad absorption over the whole range measured (in n-propanol, n-butanol and n-pentanol with weak maxima in the u.-v.) corresponds to trapped radicals formed in the radiolysis together with trapped electrons.