ELECTRONIC-STRUCTURE AND SPECTRAL PROPERTIES OF N-ANTHRYL SUBSTITUTEDPYRIDINIUM CATIONS

N-(1-anthryl)-pyridinium cations show an unusual absorption and emissi on behaviour which is investigated here using quantum chemical calcula tions (AM1 and CNDO/S-CI). The structures and properties are compared to the parent anthracene and pyridinium moieties, and the additional b and can be assigned to a transition of charge transfer type associated with orbitals localized on different subchromophores. The ground stat e potential surface indicates a highly twisted equilibrium structure f avouring orbital localization.