• Macromolecular Research
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• 제10권5호
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• pp.286-290
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• 2002

The FT-Raman spectra of trans-polyacetylene films doped lightly with iodine were obtained with the 1320-nm laser line. The observed Raman bands are attributed to positively charged domains created by acceptor doping. The observed Raman wavenumbers of the V$_2$, (CC stretch), V$_3$, and V$_4$ bands (mixed of CC stretch and CH in-plan bending) of iodine-doped form are slightly higher than those of the corresponding bands of pristine trans-polyacetylene, whereas the contrary is the case for V$_1$, and (C=C stretch) of iodine-doped form. In particular, these upshifts of the V$_2$ and V$_3$ bands are distinguished from the downshifts of these bands in donor doping. The origin of doping induced Raman bands is discussed in terms of solitons and polarons.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1404-1408
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• 2002

The resonance Raman spectra of trans-polyacetylene films doped heavily with electron donor (Na) and acceptor (HClO4) have been measured with excitation wavelengths between 488- and 1320-nm, and the relationships between the Raman excitation photon energies (2.54-0.94 eV) and its wavenumbers were discussed. We found the linear dependence of the Raman shifts with the exchanges of excitation photon energies. In particular, the Raman wavenumbers in the C=C stretching $(V_1$ band) showed a dramatic decrease with the increase in Raman excitation photon energies. In the case of acceptor doping, its change is larger than that of donor doping. The observed wavenumber (1255-1267 $cm^{-1}$) of the $V_2$ band (CC stretch) of Na-doped form is lower than that of the corresponding band (1290-1292 $cm^{-1}$) of its pristine trans-polyacetylene, whereas the contrary is the case for the HClO4 doped form (1295-1300 $cm^{-1}$). The origin of doping-induced Raman bands is discussed in terms of negative and positive polarons.

• Macromolecular Research
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• 제15권1호
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• pp.5-9
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• 2007

The attenuated total reflection infrared (ATR-IR) spectra of trans-polyacetylene (trans-PA) film doped with sodium (n-doping) were observed in the range of 1900 to $700cm^{-1}$. The observed IR bands were attributed to negatively charged domains created by n-doping electrons. The doping-induced IR bands showed considerable difference from its pristine film. After doping, the out-of-plane CH deformation band of the strong $1010cm^{-1}$ region in the pristine film disappeared while several new bands were observed at 1600 (due to C=C stretching), 1400 (due to in-plane CH bending), 1290 and 1174 (due to CH stretching), and $880cm^{-1}$ (due to CC stretching) regions for Na-doped PA. In particular, a weak band of C=C stretching at $1600cm^{-1}$ was newly obtained for the first time in the present study. The electro conductivity of the doped trans-PA film was $10^2S/cm$ and the origins of doping-induced IR bands are discussed in terms of solitons and polarons.