Quantum computational, linear and non-linear optical properties of spin-coated nickel (II)-tetraphenylporphyrin/FTO thin films

Abstract

Abstract The out of a plane (OOP) distortions in the geometric structure of Nickel (II) tetraphenylporphyrin (NiTPP) were calculated by quantum chemical calculation using semi-empirical PM3, PM6, and DFT methods. NiTPP thin films were deposited onto FTO substrates using the spin coating method on different thicknesses (80, 120, and 170 nm). The x-ray diffraction (XRD) patterns for all thicknesses exposed that NiTPP/FTO films were in the tetragonal phase structure. As the thickness grows, the crystallite size rises, and film morphology looks to be uniform and the small grains start to agglomerate to form big grains. The Raman spectra were checked and assigned for the powder and various thicknesses NiTPP/FTO thin films in the spectral range between 200−1800 cm−1. According to Tauc’s relation, the indirect energy bandgaps values were decreased as the film thickness rises. The optical constants (n& k), electronic polarizability α e the complex dielectric constant (e1& e2), and optical conductivity σ o p t were calculated as a function in film thickness. In addition, the nonlinear susceptibility χ ( 3 ) , non-linear refractive index χ ( 3 ) , and nonlinear absorption coefficient (βc) were estimated in the wavelength range 300−1000 nm by semi-empirical calculation. The findings obtained indicate that the spin-coated NiTPP/FTO thin films exhibit strong nonlinear optical (NLO) properties that are probable candidates for optoelectronic devices fabrication.