Changes in the optical properties of conducting polydiacetylene THD brought on by doping

Changes in the optical properties of conducting polydiacetylene THD (poly-1,1,6,6-tetraphenylhexadiindiamine) brought on by doping are investigated for the first time. Spectral dependences of the extinction coefficients were studied in the range 400–25 000 cm⁻¹ both for the undoped polymer (σ<10⁻⁹ S/cm) and at various doping levels (up to σ∼5×10⁻³ S/cm). The results obtained attest to the appearance of high carrier concentrations in polydiacetylene THD with conductivities σ⩾10⁻⁴ S/cm. The relatively low observed macroscopic conductivity is explained by the complex hierarchy of structural formations that are intrinsic to polymers. The results obtained are compared with the corresponding data for conducting polyacetylene. Fiz. Tverd. Tela (St. Petersburg) 40, 1162–1166 (June 1998)