The electronic structure of carcinogenic dibenzopyrenes: Linear dichroism,fluorescence polarization spectroscopy and quantum mechanical calculations

In studies of polycyclic aromatic hydrocarbon carcinogenicity three dibenzo pyrenes have been named as the strongest mutagens together with the frequen tly studied benzo[cr]pyrene. A detailed study of the electronic structure o f one of the three compounds, dibenzo[a,i]pyrene, was performed several yea rs ago, Here we Present a similar study of the two remaining compounds, dib enzo[a, h]pyrene and dibenzo[a,c]pyrene. The studies include electronic lin ear dichroism spectra, fluorescence polarization spectra and quantum mechan ical calculations for both molecules, as well as vibrational linear dichroi sm spectra for the former of the two.