Crystal Structure, and Magnetic and Fluorescence Properties of a New Terbium(III) Complex, [Tb(L)3(2,2′-bipy)(DMF)]•(2,2′-bipy)

A new Tb(III) complex, [Tb(L)(3)(2,2'-bipy)(DMF)]center dot(2,2'-bipy) (1), has been synthesized with 2-benzoylbenzoic acid (EEL) and 2,2'-bipyridine (2,2'-bipy) as ligands. In 1, the Tb(III) ion is coordinated by nine atoms to give a distorted tri-capped trigonal-prismatic geometry. The magnetic and fluorescence properties of 1 are discussed. Compound 1 is paramagnetic in the temperature range of 300 24 K, and when the temperature decreases from 22 to 2 K, it exhibits weak ferromagnetism. The compound shows four intense fluorescence emission bands arising from the transitions of Tb3+: D-5(4) -> F-7(6) (492 nm), D-5(4) -> F-7(5) (546 nm), D-5(4) -> F-7(4) (590 nm) and D-5(4) -> F-7(3) (622 nm) with an excitation wavelength of 315 mu.