Synthesis, structural characterization and luminescence studies of a novel europium(III) complex [Eu(DBM)3(TPTZ)] (DBM: dibenzoylmethanate; TPTZ: 2,4,6-tri(2-pyridyl)-1,3,5-triazine)

A novel Eu(III) complex featuring three dibenzoylmethanate (DBM) ligands and a Lewis base ligand 2,4,6-tri(2-pyridyl)-1,3,5-triazine (TPTZ) was synthesized. This novel complex was characterized by 1H NMR, FAB-MS, and elemental analyses. The structure of the complex was established by single crystal X-ray diffraction. The nonacoordinate europium ion features six oxygen atoms of the three DBM ligands and three nitrogen atoms from the TPTZ ligand, forming a distorted monocapped square antiprism. Spectroscopic studies revealed that the electronic absorption of the complex is essentially ligand-based, while the emission is characteristic of a Eu(III) ion. It is concluded that the metal-centered red emission is promoted by the ligand-assisted energy transfer, namely the antenna effects.