Synthesis, Characterization, and Luminescence of Europium(III) Schiff Base Complexes¹a

New EuIII Schiff base compounds and polyelectrolytes luminesce with quantum yields consistent with the intramolecular energy transfer mechanism established for EuIII β-diketone complexes. The emission spectra clearly show that the two EuIII ions in Eu2L3 complexes, where L is a tetradentate Schiff base ligand, are in different environments, that the Na[Eu(L)2] complexes exhibit higher quantum yields than the corresponding Eu2L3 species, and that luminescence is negligible when the ligand triplet-state lies below the 5Do state of EuIII.