Hydrothermal synthesis, crystal structure and luminescence properties of lanthanide fumarate coordination polymers containing 2,2′-bipyridine

Lanthanide coordination polymers with fumarate and 2,2'-bipyridine, [Ln(2)(C4H2O4)(3) (2.2'-bpy)(2)(H2O)(2)](n) (Ln=Sm (1), Dy (2), C4H2O42- = fumarate: 2,2'-bpy = 2,2'-bipyridine) been prepared by hydrothermal reactions and characterized by X-ray diffration. Lanthanide ions are coordinated by five oxygens of Fumarate groups, one oxygen of water and two nitrogens from 2,2'-bpy. Lanthanide ions bridged by fumarate groups in tridentate and tetradentate coordination modes form a 2-D layer structure. Hydrogen bonds and pi-pi stacking between 2-D layer result in 3-D supramolecular structure. The complexes exhibit luminescence characteristic of Sm3+ ion and Dy3+.