Synthesis and characterization of the structural and optical properties of mixed complexes of thenoyltrifluoroacetonate and diphenylphosphinates ligands with trivalent rare earth ions

• Grant number: 19/11345-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2019
• End date: July 31, 2022
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Marco Aurélio Cebim
• Grantee: Douglas Scarabello
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Neutral coordination compounds of ²-diketones with trivalent rare earth ions are extensively investigated because of their unique optical properties. However, the presence of two water molecules in these complexes may contribute to the suppression of luminescence due to the coupling of vibrational levels of O-H bonds with rare earth (III) emitting levels. A strategy widely used in the literature to optimize the luminescent properties of these complexes is to replace the two water molecules with a binder that does not have O-H bonds. From this perspective, an interesting ligand for substitution, owing to its structural properties of forming nanostructured coordination polymers 1D1, is diphenylphosphinate. Thus, this research project proposes to optimize the optical properties of the coordination compound [Eu(tta)3(H2O)2] by replacing the two water molecules with a diphenylphosphinate molecule. In addition, the insertion of this new ligand opens the perspective of the study of the structural properties of the complexes formed. The obtained compounds will be analyzed by the techniques of: I) complexiometric titration; II) thermal analysis; III) vibrational absorption spectroscopy in the infrared region; III) Raman scattering spectroscopy; IV) color index; V) high-resolution scanning electron microscopy; VI) X-ray diffraction; (VII) diffuse reflectance spectroscopy in the ultraviolet-visible region; VIII) photoluminescence spectroscopy.