Electronic energy transfer in linear polymers randomly labelled with chromophores Original Research Article

The fluorescence dynamics of chromophores randomly attached to an isolated flexible polymer chain was studied. For immobile chains (i.e., when the polymer chain conformation does not change during the excited state lifetime of the donor chromophore) analytical equations for the donor decay curves were obtained for both pseudo-ideal (Gaussian) and self-avoiding walk (SAW) polymer chain models. It is also concluded that the inhomogeneous broadening of chromophore spectra must be taken into account for ratios of the inhomogeneous to homogeneous spectral widths larger than 0.2. The luminescence of mobile chains was obtained in the limits of slow and fast diffusion. The donor-to-donor excited state transport was also studied for polymers randomly labeled with a single chromophore. The ensemble average probability that an originally excited chromophore is still excited at time t was obtained for frozen chains with both gaussian and SAW conformational distributions.