Crystal Structure and Properties of a Terbium Benzoate Complex with 1,10-Phenanthroline

A terbium benzoate complex with 1,10-phenanthroline Tb(ba)3(phen)]2, where ba = benzoate and phen = 1,10-phenanthroline, has been prepared and structurally characterized by X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 10.7881(5), b = 11.9262(6), c = 12.4249(6) A,α = 105.1260(10),β = 93.6010(10), γ = 113.3350(10)o,(C33H23N2O6Tb)2, Mr = 1404.90, V = 1391.8712 A3, Z = 1, Dc = 1.676 g/cm3,μ(MoKα) = 2.590 mm-1, F(000) = 696, the final R = 0.0277 and wR = 0.0670 for 6085 observed reflections with I > 2σ(I). The crystal consists of binuclear molecules of the title compound. Each Tb3+ ion is nine-coordinated to one 1,10-phenanthroline molecule, one bidentate carboxylate group and four bridging carboxylate groups. The carboxylate groups are bonded to the terbium ion in three modes: the chelating bidentate, bridging bidentate and bridging-chelating tridentates. Excitation and luminescence data observed at room temperature show that the title complex emits very intensive green fluorescence under ultraviolet light. The results of thermal analysis indicate that the complex Tb(ba)3phen]2 is very thermal stable.