| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1440085 | Synthetic Metals | 2016 | 6 Pages |
•Photoluminescence (PL) measurements of a statistical copolymer poly-(p-arylene ethynylene)-alt-poly (p-arylene-vinylene)s (AnE-PVstat) thin film within a temperature range between 10 and 300 K.•A modified Franck Condon (FC) progression with variable 0-0 peak intensity is used to reproduce the experimental PL spectra.•From the fit, we have determined the variation of the scaling factor αα(related to the amplitude of the 0-0 transition peak), the electronic transition energy E0E0and the disorder parameter σσ with temperature.•Comparison between theoretical and experimental dependence of the spectral shiftΔε(T)Δε(T)normalized toσ(T)σ(T)versus kTσ(T)used to indicate that two processes promotes the spectral diffusion in AnE-PVstat.•Dependence of the diffusion length LDLD on temperature and disorder parameterσσ, via the intermolecular separation distance d between excitonic sites involved in a thermally activated hopping.
The dependence upon the temperature of the photophysics of a statistical copolymer anthracene containing poly-(p-aryleneethynylene)-alt-poly (p-arylene-vinylene)s (AnE-PVstat) as a thin film has been investigated. For this purpose, photoluminescence (PL) spectra have been recorded in a temperature ranging between 10 and 300 K. A modified Franck-Condon model has been invoked to analyze the PL spectra. Our findings point out that upon increasing temperature several vibrational modes are activated starting from a transition temperature leading to molecular rearrangements which leads in turn to a decreased intermolecular distance. The latter fact is consistent with the exciton dynamics which has been found to be governed only by a prompt downhill migration to the exciton band edge at low temperatures up to a transition temperature above which a thermally activated hopping process takes place after the downhill migration.
