Structural and optical properties of nanocrystalline platinum octaethylporphyrin (PtOEP) thin films

Abstract

Thermal evaporation technique was used to prepare the Platinum octaethylporphyrin (PtOEP) thin films. X-Ray Diffraction (XRD), Transmission Electron Microscope (TEM) and Fourier-transform infrared techniques (FT-IR) were used to study the crystal and molecular structure of PtOEP, the results confirmed that the PtOEP thin films have nonostructural features. Extinction coefficient, k and refractive index, n were estimated using spectrophotometric measurements of both transmittance T (λ) and reflectance R (λ) at normal incidence light in the wavelength range 200–1100 nm. The absorption parameters such as molar extinction coefficient, εmolar, oscillator strength, ƒ and electric dipole strength, q2, the type of electronic transition, optical energy gap and fundamental energy gaps were reported. The normal dispersion (λ > 600 nm) of refractive index is discussed in terms of single oscillator model of Wemple–Didomenico. The dispersion and the dielectric characterizations of the thin films were investigated and discussed.