Novos compostos de coordenação luminescentes contendo Eu3+ e Tb3+ e o estudo de suas propriedades espectroscópicas

Abstract

Were synthesized novel luminescent coordination compounds of rare earth containing triazines, pyridines, imidazoles and triazoles as ligands. After isolation, the complexes of europium, terbium and gadolinium were characterized by elemental analysis (C, H, N, S), mass spectrometry coupled with ion cyclotron resonance Fourier transform, thermogravimetric analysis, infrared and luminescence (emission, excitation, lifetime and chromaticity) spectroscopy. The complexes exhibit coordination through oxygen and nitrogen ligands and their molecular compositions were calculated using composition analysis. Phosphorescence data complexes of Gd3+ showed that the triplet states of the ligands have higher energies than the major emitting states of Eu3+ ions ( 5D0) and Tb3+ ( 5D4), indicating that these ligands can act as an energy donor through the antenna effect for these ions. They also determined the efficiencies and quantum yields of issue of the emitting level of Eu3+ . In relation to the compounds of Tb3+ , the data showed high photoluminescence emission intensity of the characteristic transitions 5D4?7 FJ (J=0-6), confirming that the ligands investigated are good sensitizers. The new complexes of RE3+ can act as molecular devices light converters promising luminescent materials for a wide range of optical applications.