Abstract: Some novel binary and ternary complexes of rare earth(Gd, Eu ,Tb) with N Phenylanthranilic acid and 1,10-Phenanthroline were synthesized by homogenous precipitation and their compositions were characterized by elemental analysis, IRspectra and UV-Vis spectra. The triplet state energies of N-Phenylanthranilic acid was determined to be 24330 cm^-1 with the phosphorescence spectra of its gadolinium complexes and the energy match between the ligand and the central rare earth ions was studied. The photophysical properties such as luminescence properties and intramolecular energy transfer match between rare earth ions and ligands and between ligands were discussed. The result indicates that terbium complexes with N-Phenylanthranilic acid and 1,10-Phenanthroline have excellent luminescence properties.

Key words: Rare earth complexes, N-Phenylanthranilic acid, 1,10-Phenanthroline, Photophysical properties