Synthesis and luminescence of a series terbium ternary complexes with 1-phenyl-3-methyl-4-acyl-5-pyrazolones

A series of terbium ternary complexes with 4-acyl substituted pyrazolones: Tb(L)(3).2H(2)O and Tb(L)(3).Dipy, where L = 1-phenyl-3-methyl-4-acetyl-5-pyrazolone (PMAP), 1-phenyl-3-methyl-4-propionyl-5-pyrazolone (PMPP), 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone (PMIBP), 1-phenyl-3-methyl-4-pivaloyl-5-pyrazolone (PMPVP) and 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP), Dipy = 2,2'-dipyridyl, were synthesized and identified by elementary analysis, The complexes were characterized by FT-IR, UV-Vis spectra and TG-DTA analysis, The luminescences from both the solid state and solution were studied and their fluorescence lifetime was determined by using the frequency-domain method, The results show that both fluorescence intensities and lifetime of these complexes strongly depend on the structure of the substituted 4-acyl groups, The fluorescence intensities of the alkyl acyl substituted pyrazolone terbium complexes are three orders magnitude stronger than that of Tb(PMBP)(3).2H(2)O, and the introduction of the neutral ligand (Dipy) can enhance the fluorescence intensities of the complexes.