Influence of Thickness on Optical Properties of (PVA- CoCl2) films

Abstract

(PVA- CoCl2) films with different thicknesses were prepared by casting method. The thickness of the
prepared films were 15, 25, 35 and 45 µm .The optical transmission (T %) in the wavelength range 190-900
nm of films deposited was measured. The results show that The absorption coefficient α ‹104
(cm-1 ) .These films show indirect allowed transitions , the optical energy gap about (4.31 eV) for (15 µm),(4.51 eV) for (25 µm) ,(4.68 eV) for (35µm) and (4.72 eV) for (45 µm). The real and imaginary part of dielectric constant
calculated and correlated with thicknesses.