Polypyrrole band structure upon doping

Figure 1.10 Evolution of the polypyrrole band structure upon doping (a) low doping level, polaron formation (b) moderate doping level, bipolaron formation (c) high doping level (33 mol%), formation of bipolaron bands. (Reprinted with permission from Accounts of Chemical Research, 18, 309. Copyright (1985) American Chemical Society.)...

Bredas, J.L., et al. 1984. Polarons and bipolarons in polypyrrole Evolution of the band structure and optical spectrum upon doping. Phys Rev B 30 1023. 

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