Abstract
In this study, poly(vinyl alcohol) (PVA) films doped with thorium nitrate hydrate [Th(NO3)(4)] have been prepared using casting technique. The optical absorption spectra were recorded at room temperature in the wavelength range 200-800 nm. From the absorption edge studies, the values of the Urbach energy (E-u) have been evaluated. These energy values vary slightly with composition, indicating that the model based on electronic transitions between localized states is not preferable. Optical parameters such as refractive index and complex dielectric constant have been determined. The dispersion of the refractive index is discussed in terms of the single-oscillator Wemple-DiDomenico model. Color properties of the prepared samples were discussed in the framework of CIE L*u*v* color space. (C) 2013 Society of Plastics Engineers