Evaluation of the Optical and Structural Properties of Constructed Bis-indole Derivatives Using (Sm2O3/SiO2) Catalyst

(SiO2/Sm2O3) was successfully synthesized and examined using scanning electron microscopy; X-ray diffraction and Fourier transform infrared spectroscopy. Obtained data shows the formation of crystalline phase superimposed over the silicate amorphous matrix. The synthesized catalyst was used for eco-friendly synthesis of bis-indole derivatives. Two moles of indole and different aromatic aldehyde were mixed and heterocyclic aldehydes have been adopted in-expensive, recyclable, easily prepared and nontoxic catalyst (SiO2/Sm2O3) under solvent free conditions. The chemical structures of the synthesized compounds have been introduced and correlated with UV/vis. optical absorption spectra in combination with (HOMO-LUMO) through experimental spectrophotometric data in both direct-indirect transitions and that obtained based of density functional theory (DFT).