Ultraviolet absorption spectra of the 2-phenylethyl radical formed during pulse radiolysis

2-Phenylethyl radicals were prepared by the decarboxylation reaction of 3-phenylpropanoic acid with sulfate radical ions formed during the pulse radiolysis of aqueous solutions containing peroxydisulfate ions. The ultraviolet absorption spectrum of the transient radicals consisted of a band centred at 309nm with an extinction coefficient of 50001.mol-1cm-1. Attempts were made to form phenylethyl radicals by the electron-attachment dissociation reaction of (2-haloethyl)benzenes. Contrary to literature reports, it was found that the latter reaction does not occur in either cyclohexane, benzene or aqueous solutions of (2-chloroethyl)- and (2-bromoethyl)-benzenes