A binuclear terbium complex with 2,4,6-Trimethylbenzoate and 1,10-phenanthroline, [Tb-2(TMBA)6(Phen),], has been synthesized (TMBA=2,4,6-Trimethylbenzoic acid and phen=1,10-phenanthroline) and characterized by IR, elemental analysis and X-ray diffraction methods. The title complex crystallizes in monoclinic system, space group P2(1)/c with a=1.327 5(2) nm, b=2.817 9(5) nm, c=1.282 5(2) nm, beta=1 16.692(3)degrees, V=4.286 2(13) nm(3), Z=4, D-c=1.423 g center dot cm(-3). There are four bridged carboxylate groups of the 2,4,6-trimethylbenzoic acid bonded to the two terbium ions, each ions is als...