Effect of temperature and oxygen on luminescence spectra and polarization of divinylbenzoxazolylbiphenyl thin films.

H-type molecular aggregation as assembly with chromophore dipoles arranged parallel to each other has been observed in absorption and luminescence spectra of divinylbenzoxazolylbiphenyl thin films deposited on quartz glass substrate by thermovacuum method. The reversible changes of fluorescence anisotropy have been observed under film heating below the glass transition temperature correlating with lifetime changes. The addition of oxygen was found to cause an essential luminescence quenching. The hexyloxy group in the side chain of dibenzoxazolylbiphenyl molecule decreases H-type molecular aggregation and energy migration, and increases luminescence quenching induced by adsorbed oxygen owing to the formation of more porous film morphology.