Relevance between structure and spectroscopic studies, along with enhanced NLO response of porphyrin complexes and hybrid nanostructures

Due to the characteristic property of porphyrins, which is the formation of complexes with metal ions, this work investigated the spectroscopic and nonlinear optical properties of octaethylporphyrins with different substituents: platinum, ruthenium carbonyl, ferric chloride and palladium. The relationships between the surface of thin films prepared by spin coating technique, studied with an atomic force microscope, and the optical properties are described in this paper. Herein, the strong influence of absorption properties on the nonlinear optical response of the studied porphyrin complexes is presented. NLO properties, investigated by means of second and third harmonic generation, as well as the Z-scan technique are represented, while NLO coefficients have been determined using theoretical formulas, demonstrate the usefulness of porphyrin complexes as potential materials for nonlinear optics applications. Moreover, this work presents studies of the nonlinear optical properties of a metamaterial consisting of a nanoporous membrane and selected porphyrin complex. The extraordinary NLO response of the studied nanocomposite demonstrate its usefulness in the field of both nonlinear optics, as well as nanophotonics and physics of metamaterials.