The optical properties and spectral behavior for pure and doping thin films of Malachite green were studied using Cecil Reflecta-Scan CE-3055 Reflectance Spectrometer measurements of the transmissivity and reflectivity at normal incidence of light in the wavelength range 300–1000 nm in steps of 2 nm. The refractive index, n, and absorption index,k, were calculated and it was found that they are dependent on film doping in the thickness 1 μm. The absorption spectra in the UV–VIS region has been analyzed in terms of both molecular orbital and band theories. The direct energy gap was obtained and equals to 2.667 eV , 2.672eV, 2.678 eV , 2.638 eV and 2.627 eV for pure , Sodium borohydride (S2 and S3) and Iodine (S4 and S5) doping thin films, respectively. The real 1 e and imaginary 2 e parts of the dielectric constant, the optical conductivity opt s , electrical conductivity e s the thirdorder nonlinear optical properties χ (3) and nonlinear refractive index were calculated for doping and pure Malachite green thin films.
