Three novel microporous 3D heterometallic 3d–4f coordination polymers: Synthesis, crystal structures and photoluminescence properties

Three novel 3D microporous heterometallic coordination polymers, [LnZn(imdc)(ip)(H2O)2]·3H2O [Ln = Nd (1), Eu (2), Gd (3); H3imdc = imidazole-4,5-dicarboxylic acid; ip = isophthalate], have been synthesized under hydrothermal conditions. X-ray crystal structure analyses reveal that compounds 1–3 are isomorphous and crystallize in the monoclinic space group P21/c. The crystal structures constructed from Zn-imdc step-like chains and 2D [LnZn(imdc3−)]n layers and ip ligand, which giving rise to a 3D framework that consists of two types of 1D open channels, with 5.2 × 8.6 Å channels along the a axis and 8.6 × 10.2 Å channels along the b axis. The luminescence properties of complex 1 and 2 have also been investigated.