Infrared Photoacoustic Spectroscopy of Conducting Polymers. I. Undoped and n-Doped Polyacetylene

Abstract
Fourier transform infrared photoacoustic (FT-IR-PA) spectroscopy has been used to obtain the first published infrared spectrum of a heavily n-doped polyacetylene. Comparisons are made with the FT-IR-PA spectrum of undoped polyacetylene. All the infrared peaks in the FT-IR-PA spectrum of undoped polyacetylene agree in wavelength to ±10 cm−1 with transmission infrared peaks previously assigned by Shirakawa and Ikeda. Spectral shifts and intensity differences between the n-doped and undoped polyacetylene are similar to changes noted previously in the infrared spectra of p-doped polyacetylenes.