Synthesis, crystal structure, vibrational spectra, optical properties and theoretical investigation of a two-dimensional self-assembled organic-inorganic hybrid material

Abstract

Organic–inorganic hybrid material of formula (C4H3SC2H4NH3)2[PbI4] was synthesized and studied by X-ray diffraction, Infrared absorption, Raman scattering, UV–Visible absorption and photoluminescence measurements. The molecule crystallizes as an organic–inorganic two-dimensional (2D) structure built up from infinite PbI6 octahedra surrounded by organic cations. Such a structure may be regarded as quantum wells system in which the inorganic layers act as semiconductor wells and the organic cations act as insulator barriers. Room temperature IR and Raman spectra were recorded in the 520–3500 and 10–3500 cm−1 frequency range, respectively. Optical absorption measurements performed on thin films of (C4H3SC2H4NH3)2[PbI4] revealed three distinct bands at 2.4, 2.66 and 3.25 eV. We also report DFT calculations of the electric dipole moments (μ), polarizability (α), the static first hyperpolarizability (β) and HOMO–LUMO analysis of the title compound investigated by GAUSSIAN 09 package. The calculated static first Hyperpolarizability is equal to 11.46 × 10−31 esu.