10.1021/jp3096242.s001
Norihiko Takeda
Norihiko
Takeda
John R. Miller
John R.
Miller
Poly(3-decylthiophene)
Radical Anions and Cations
in Solution: Single and Multiple Polarons and Their Delocalization
Lengths in Conjugated Polymers
American Chemical Society
2012
THF
P 3DT chain
Conjugated PolymersOptical absorption spectra
P 3DT
pulse radiolysis
polaron
2012-12-20 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Poly_3_decylthiophene_Radical_Anions_and_Cations_in_Solution_Single_and_Multiple_Polarons_and_Their_Delocalization_Lengths_in_Conjugated_Polymers/2459005
Optical absorption spectra of anions and cations of poly(3-decylthiophene)
(P3DT) in solution were identified as single polarons. Pulse radiolysis
of P3DT in THF determined the spatial extent of one negative polaron
to be ∼11.5 thiophene units by observing transient absorption
of P3DT<sup>–•</sup> radical ions, which are prinicpally
free ions, at 850 nm with ε = (7.25 ± 0.47) × 10<sup>4</sup> M<sup>–1</sup> cm<sup>–1</sup> and bleaching
of the neutral absorption band at 450 nm. P3DT<sup>–•</sup> was formed in a combination of diffusive reactions and fast “step”
processes. Similarly, a positive polaron of P3DT was estimated to
delocalize over ∼8.7 thiophene units by pulse radiolysis in
chloroform. Chemical reduction by sodium and oxidation by FeCl<sub>3</sub> injected multiple charges into a single P3DT chain while
showing absorption spectra in the early stages of reaction resembling
those observed by pulse radiolysis. The results indicated that multiple
polarons exist in a single chain of P3DT before coalescing into bipolarons
or transforming into other forms of polaron.