Dual-ligand approach to synthesize a new 3-D heterometallic framework consisting of dysprosium–carboxyl belt and inorganic copper–iodine chain

A novel three-dimensional (3-D) Dy(III)–Cu(I) heterometallic polymer, [Dy2(pca)2(npa)2(H2O)3](Cu2I2) (1, pca = 2-pyrazinecarboxylic acid, npa = 1,8- naphthalenedicarboxylic acid), has been synthesized by hydrothermal reactions of Dy2O3, CuI, 2-pyrazinecarboxylic acid, 1,8-naphthalene anhydride in water in the presence of HClO4. Compound 1 has been characterized by elemental analysis, infrared spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analysis, respectively. The thermal stability and luminescence property of compound 1 have also been studied. Single crystal X-ray diffraction analysis reveals that compound 1 contains two distinct units of 1-D Dy–carboxyl belt and Cu–I chain. The two types of 1-D units are further linked via pca ligands to give a heterometallic Dy–Cu framework.