Síntese, caracterização estrutural e estudo fotoluminescente de nove novos cetoprofenatos dos lantanídeos Eu3+, Gd3+ e Tb3+ contendo ligantes N,N’-doadores

Abstract

Coordination compounds of lanthanides have been the subject of intense research in recent decades, particularly from the perspective of constructing complex materials with diverse physicochemical properties and specific functions. Due to their luminescent properties, lanthanide carboxylates containing nitrogenous ligands have great potential to be used as Light-Converting Molecular Devices (LCMDs), which can be applied in the fabrication of OLEDs (Organic Light-Emitting Diodes) used in electronic device screens, chemical sensors, medicine, among various other areas. In this context, the present work carried out the synthesis, structural characterization, and photoluminescent study of nine (9) new carboxylates of Eu3+, Gd3+, and Tb3+ derived from the non-steroidal anti-inflammatory drug ketoprofen, containing the auxiliary N,N’-donor ligands: 2,2’-bipyridine (bpy), 1,10-phenanthroline (phen), and 4,4’-dimethyl-2,2’-bipyridine (4,4’-dmbpy). The synthesized compounds were characterized using various analytical and spectroscopic techniques, such as: elemental analysis (%C, H, and N), vibrational spectroscopy in the infrared region (FTIR) and Raman, thermal analysis (TG curves), powder X-ray diffraction (PXRD), and photoluminescence spectroscopy (PL), where excitation and emission spectra, as well as luminescence lifetimes, were obtained. Additionally, the semi-empirical Sparkle method was used to obtain the ground state geometries of the Eu3+ complexes, which were used to calculate various luminescence parameters and compared with those obtained experimentally. These parameters showed excellent agreement with those obtained experimentally.