THEORETICAL-STUDY OF CYCLIC CONJUGATION IN PHENES - SOME HITHERTO UNNOTICED FEATURES

Cyclic conjugation in phenes is examined by means of the Bosanac-Gutma n-Aihara method. In contrast to the predictions based on the analysis of Kekule or Clar structures, we find that when going along the hexago ns of a phene molecule, cyclic conjugation varies in a rather non-unif orm manner. In contrast to a number of other homologous series of benz enoid hydrocarbons, the intensity of cyclic conjugation in phenes incr eases when going towards the center of the molecule.