FLUORESCENCE SPECTROSCOPY OF OLIGO(ANTHRYLENEVINYLENES)

Fluorescence spectra of oligo(anthrylenevinylenes), matrix-isolated in low-temperature MTHF glasses, have been recorded employing the site-selection technique. Comparison with the spectroscopic properties of members of the phenylenevinylene family indicates that replacement of a phenylene by an anthrylene moiety causes both a significant depression of the optical transition energy counteracted by a large increase of inhomogeneous band broadening due to variations of the intramolecular twist of the molecules in all-trans conformation. The latter is responsible for both elastic and inelastic relaxations of the molecules after optical excitation.