Optical and dielectric studies for the determination of gap states of the 'polypyrrole'

The polypyrrole is a conducting polymer prepared by chemical route. The diffuse reflectance measured in the wavelength range (300-2500 nm) permitted the calculation of the refractive index (n), extinction coefficient (k), dissipation factor (tan δ) and relaxation time (τ). The optical band gap (E g) was evaluated from the dielectric and conductivity properties, and its value (1.01 eV) was confirmed by using the Tauc relation.