Theoretical vibrational spectra of the leucoemeraldine form of neutral reduced polyaniline are presented, based on a single-periodic-chain model and a harmonic potential with parameters transferred from the molecules dyphenylamine and N,N’-diphenyl-p-phenylenediamine. The out-of-plane degrees of freedom and the infrared-absorption intensities are included in the calculations. Several experimental spectra are analyzed and compared with the theoretical ones. Our comparative analysis enables conclusions concerning packing density, spatial and electronic structure, and electron-phonon coupling of the samples of different origin.

• Received 25 July 1991

DOI:https://doi.org/10.1103/PhysRevB.45.728