A complex [Sm（2-IBA）2（2,2’-bipy）（NO3）]2 （2-HIBA=2-idobenzoic acid; 2,2’-bipy=2,2’-bipyridine） was synthesized by solvent method and characterized by X-ray single-crystal diffraction. The complex crystallized in triclinic crystal system, Pī space group, with a= 0.97873（3） nm, b=1.28124（3） nm, c=1.29174（3） nm, α=108.3740（10）o, β=111.7340（10）o, γ=101.7870（10）o. The complex was the centrosymmetric binuclear molecule, in which two Sm3＋ ions were connected by four 2-IBA ligands. Two of the 2-IBA ligands were in a bidentate bridging mode and the other two were in a tridentate bridging mode. Sm3＋ ion was also coordinated to one chelating NO3– group and one 2,2’-bipy molecule. The 2D supramolecular network formed through weak I…I interactions and π…π stacking interactions. The fluorescent emission peaks at 562, 595, and 642 nm corresponded to the 4G5/2→6F5/2, 4G5/2→6F7/2, and 4G5/2→6F9/2 transitions of Sm3＋ ion, respectively.
