Resonance Raman spectra of polyaniline (PAn) in different forms (base

doped

dedoped

reduced and oxidized) were determined. According to the spectral features and other experimental results

it was found that the molecular chain of the doped PAn consists of two kinds of N atoms and three kinds of aromatic rings with different charge distribution. The effect of the oxidation extent of the PAn chain on the doping efficiency was observed. Thus the "Four-ring BQ derivatives" model and corresponding doping reactions were proposed.