Three 3d–4f heterometallic coordination polymers based on polydentate ligand and sulfate: Synthesis, crystal structure and photoluminescent properties

Three heterometallic coordination polymers [Gd2Cu(Hbidc)2(SO4)2(H2O)7]n (1), [Eu2Cu(Hbidc)2(SO4)2(H2O)7]n (2), and [Dy2Cu(Hbidc)2(SO4)2(H2O)7]n (3) (H3bidc = 1H-benzimidazole-5,6-dicarboxylic acid) have been synthesized under hydrothermal conditions. They are characterized by elemental analysis (EA), infrared (IR) spectroscopy, thermogravimetric analysis (TGA), single crystal X-ray diffraction, and power X-ray diffraction (XRD). The results reveal that all complexes present almost identical three-dimensional (3D) PtS topology framework structures. The photoluminescent properties of 2 and 3 are investigated.