Investigation of luminescence in new blue-emitting poly(2',5'-dioctyloxy-4,4',4''-terphenylenevinylene)s

The dependence of the linear optical properties of some soluble poly(terphenylenevinylene)s on the relative amount of cis- and trans-vinylene units has been investigated. A regular blue-shift of the absorption spectra in solution has been observed upon the addition of cis double bonds. Luminescence spectra show a vibronic structure which accounts for the reduced inter-ring torsion in the excited state with respect to the ground state. Moreover, an increased electron–phonon coupling for cis-rich polymers has been observed.