POLARIZED ABSORPTION-SPECTRA OF AROMATIC RADICALS IN STRETCHED POLYMER FILM .2. RADICAL IONS OF ANTHRACENE AND PYRENE

Radical anions and cations of anthracene and pyrene are prepared in polymer film upon γ irradiation at 77 K by choosing a suitable polymer film-solvent system in which anthracene or pyrene is incorporated. Polarized absorption spectra of these radical ions are determined in stretched polymer film. It is shown that qualitatively reliable information is obtained on the polarization of electronic transition by dichroism analysis. The dichroic behavior of polarized absorption spectra of the radical anion is very similar to that of the cation and the pairing property of the ions of alternant hydrocarbons is demonstrated from the viewpoint of polarization. © 1979 American Chemical Society.