[en] The incoherent neutron scattering cross-section for a harmonic crystal can be determined from a set of frequency distributions. We compute these frequency distributions for crystalline, syndiotactic polyvinylchloride. We use the force constants introduced by Opaskar and Krimm for the saturated hydrocarbons. We also include a diagonal torsional force constant of 0.06 mdyn Å/rad² . We ignore intermolecular forces in this calculation except for the inclusion of an ϵ² dependence in the frequency distributions at small ϵ. We present representative calculations to indicate the resolution needed to determine the details of the frequency spectra. (author)