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Spectroscopic studies of dopant-induced conformational changes in poly(3-hexylthiophene) thin films

  • Annabel R. Chew (a1) and Alberto Salleo (a1)

The effect of p-type doping at ultra-low concentrations (~10−4–10−5 monomer mol fraction) of the polymer poly(3-hexylthiophene) (P3HT) is studied using charge modulation (CM) spectroscopy. Quantitative analysis of CM spectra of doped P3HT show that dopants induce measurable changes in the P3HT local chain conformation. We find that the dopants reside in both the aggregate and amorphous regions of the polymer, not just in the amorphous regions, as previously assumed. With increased doping, the P3HT intrachain disorder grows, causing the P3HT chains to become more oligomer-like, which we postulate leads to the drop in mobility commonly observed in literature.

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Address all correspondence to Alberto Salleo at
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MRS Communications
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