Synthesis, characterization, and photophysical properties of four different
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-conjugated oligomerscontaining alternate arylenevinylene and pyrrolenevinylene repeat units are reported. The optoelectronic propertiesare traced from the molecules to oligomers and to thin films and single layer electroluminescent (EL) devices.These oligomers exhibited strong absorption and emission corresponding to
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-
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* transitions which vary withelectronic nature of the aryl moieties. The band gaps of these oligomers are in the range 1.84-2.04 eV and theyemit in the orange to red region. The photoluminescence (PL) spectra of the oligomers
P1-
P4 in solution andfilm state are significantly different from each other. The time-resolved fluorescence decay in dichloromethanesolution showed a fast decay profile for the anthracene-bridged oligomer and a relatively slow decay for benzene-bridged oligomer. Polymer light emitting diodes (PLEDs) with single active layer of oligomers with theconfiguration ITO/PEDOT:PSS/oligomer/Ca/Al exhibited low turn on voltages and yellow to deep red emission.Though the anthracene-bridged oligomer did not show any detectable PL in the film state, a weak electroluminescence (EL) emission around 730 nm was observed.