Pemigraniline base

Figure 1,45. Various forms of PANl (a) leucoemeraldine base (LEB, poly(paro-phenylene amine)) (b) pemigraniline base (PNB, poly(poro-phenylene imine)) (c) emeraldine base (EB) (d) emeraldine salt (ES), bipolaron form (e) emeraldine sail, polaron form.

Photoinduced infrared absorption studies show that the photoinduced infixired modes are much weaker in intensity, than the photoinduced electronic transition [23], in contrast to the behavior of polyacetylene [51,52] and polythiophene [6]. Analysis, within the amplitude mode formalism [53], indicates that the polarons are massive, > or -60 m, while use of bond order [54] or Holstein [55] polaron formalisms leads to an even larger estimate of the mass of the polarons. Photoexcitation, into either the exciton peak or the 7C-to-7t peak of emeraldine base, produces essentially identical long-lived photoinduced infrared modes [29]. The long-lived photoinduced spectra of the leucoemeraldine base are much weaker. Similarly, the photoinduced infrared absorptions in the pemigraniline base are much weaker, than the photoinduced electronic transitions, again indicating massive photoinduced defects [30]. 

Figure 14.3 Molecular structure of PANl during protonation/deprotonation process (y=0, insulating fully oxidized pemigraniline base form y=0.5, semiconducting half-oxidized emeraldine base form y=l, insulating fully reduced leucoemeraldine form).

The mechanism of maintaining electron neutrality in a sohd fiber during a chatg-ing/discharging process has been explained by intercalation/de-intercalation of the cations between the fiber and the electrolyte and it has been claimed that the transfer of protons is not probable to achieve electron neutrality during the redox process. Therefore, the pemigraniline base oxidation state is unlikely to be formed in ionic liquid [12],... 

Quillard S, Louarn G, Lefrant S, Macdiarmid AG (1994) Vibrational analysis of polyaniline a comparative study of leucoemeraldine, emeraldine, and pemigraniline bases. Phys Rev B 50(17) 12496-12508... 

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