Synthesis, structure, and luminescence properties of rare earth complexes with β-diketone containing imidazole group

A series of lanthanide metal complexes [Ln = Sm (1 and 5), Eu (2 and 6), Tb (3 and 7), Er (4 and 8)] were synthesized with imidazole-containing β-diketone ligands. Complexes 1-8 were characterized by IR, elemental analysis, powder XRD, and TG measurements. The photoluminescence properties and the probable mechanism of the Sm, Eu, and Tb complexes were studied. The Eu complex generated strong red light in response to excitation with purple light (380-420 nm). Their fluorescence lifetime of 2 and 6 were 378 and 267 μs, respectively. The measurement and analysis of the thermal properties showed that these were thermal stable. Therefore, it can be applied to LED fluorescent powder. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)