Electronic structure and optical properties of poly[3-(4-octylphenoxy) thiophene]: experimental and theoretical studies
Résumé
This article reports the synthesis and characterization of a new polythiophene derivative phenoxy-substituted, the poly[3-(4-octylphenoxy) thiophene] (POPOT). The oxidative polymerization was found to yield low molecular weight material, whereas a modified Grignard metathesis (GRIM) yielded polymers of high molecular weights. One- and two-dimensional NMR indicated the latter to be highly regioregular. POPOTs exhibited higher thermal stabilities than equivalent alkoxy-substituted polythiophenes and exhibited red shifts in the absorption spectra with respect to equivalent. The absorption spectra showed a red shifted λmax at 540 nm in tetrahydrofuran solutions and 580 nm in spin-coated films, with respect to poly(3-alkylthiophene)s. A further red shift of 40 nm in going from solution (540 nm) to solid states (580 nm) is correlated with results from density functional theory electronic structure calculations. © 2008 Wiley Periodicals, Inc.