Comparative study of the luminescent properties of europium and terbium coordinated with thenoyltrifluoroacetone or pyridine-2,6-dicarboxylic acid in aqueous solutions

Abstract

The chelates formed with europium(III) and terbium(III) coordinated with either thenoyltrifluoroacetone or pyridine-2,6-dicarboxylic acid were studied. The formation and the composition of the chelates were compared with respect to the number of donor groups of the ligand and the coordination number of the lanthanide ion. The luminescent properties of the chelates were investigated and compared in terms of the relative luminescence intensity, the linear dynamic range and the detection limit. The results are discussed with respect to the stoichiometry of the chelate, the lifetime of the emitting level and the energy gap between the donor level of the ligand and the emitting level of the ion.