OPTICAL-PROPERTIES OF CHEMICALLY PREPARED POLYEMERALDINE

Results of the analysis of reflectance spectra in the UV-Vis-near-IR r ange of chemically prepared polyemeraldine powder samples are presente d. A new optical transition at 1.15 eV is observed for the base form o f the polymer. The polymer salt spectra are characterized by metal-lik e features at low frequencies. The real part of the dielectric functio n, epsilon1(omega), reverses sign and becomes negative at 0.8 eV. At 1 .85 eV, the extinction coefficient, kappa, and hence the imaginary par t of the dielectric function, epsilon2(omega) vanishes. This may possi bly arise from the excitation of a longitudinal plasma oscillation on the polymer surface.