Synthesis and luminescence spectral properties of europium (III) and terbium (III) complexes with a new Schiff base ligand N,N′,N"-tri-(2,4-dihydroxyl-acetophenone)-triaminotriethylamine

A new Schiff base ligand with tripodal structure, N,N',N"-tri(2,4-dihydroxyl-acetophenone)-triaminotriethylamine (H6L), and its complexes with europium (III) and terbium (III) have been synthesized. The complexes have been characterized by element analysis, IR spectra, mass spectra, thermal analysis and molar conductivity. The europium (III) and terbium (III) cations coordinate with the Schiff base nitrogen atoms, the bridgehead nitrogen atoms and phenolic hydroxyl oxygen atoms of the ligand. The luminescence properties of the complexes in DMSO, THF, DMF, MeCN and CH3OH solvents have also been investigated. Under the excitation of UV light, these complexes exhibit characteristic of europium (III) and terbium (III). The solvent factors influencing the luminescence intensity are also discussed. Tentative structures for the complexes have been proposed based on the experimental results.