Eu3+ and Tb3+ Coordination Compounds with π-conjugated Ligands: Luminescence and Structural Properties

Abstract

New lanthanide-based luminescent coordination compounds containing quinoline derivatives and 2-(4-hydroxyazobenzene)benzoic acid (HABA) were synthesized. Fourier transform infrared spectroscopy (FTIR), UV-Vis spectra, Elemental analyses, Energy dispersive X-ray fluorescence (EDXRF), and mass spectrometry (MALDI) were applied for six complexes′ structural elucidation. In addition, photoluminescence spectroscopy was performed in the solid state. Eu3+ and Tb3+ compounds linked to the π-conjugated system described energy transfer to the metal through the antenna effect. Emission spectra depicted bands at 616–617 nm, characteristics of red light for Europium complexes, assigned as hypersensitive 5D0→7F2 transition, and depicted bands at 540–542 nm (green light) for Terbium complexes, assigned as 5D4→7F5 transition.