Abstract
The interpretation of the infrared and Raman spectra of pristine polypyrrole as 1‐d lattice is presented as the result of lattice dynamical calculations. Geometries and vibrational force fields are derived from semiempirical quantum chemical calculations and/or from the optical spectra of oligomers. This paper lays the background information which are used in the second paper, which immediately follows, where the spectra of the conducting polymer are extensively discussed.