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A new copper(II)-sodium(I)-containing phosphomolybdate-based coordination framework, namely, {[EMIm][Cu1.5Na(btmx)2.5(H2O)2(HP2Mo5O23)]·0.5H2O}n (denoted as CZU-6, EMIm = 1-methyl-3-ethyl imidazolium, btmx = 1,4-bis(1,2,4-triazole-1-ylmethyl)-2,3,5,6-tetramethyl benzene), was synthesized by using ionic liquid EMIm-Br as a template under hydrothermal conditions. The X-ray structural analysis revealed that CZU-6 features the first example of 3D anionic polyoxometalate-based coordination framework with trinodal (4,4,4)-connected sqc topological net. Moreover, CZU-6 could be directly adopted as an efficient heterogeneous catalyst for the solvent-free ring-opening polymerization of e-caprolactone, and the catalyst could be easily recovered and reused several times without loss of its crystallinity and activity.

Two novel 2-D organic–inorganic hybrid silicotungstates [H2en][Cu(en)2(H2O)]2{[Cu(en)2]3[Cu(en)(ox)]2[Ln2(ox)(α-SiW11O39)2]}·nH2O (Ln = ErIII, n = 10 for 1, Ln = SmIII, n = 8 for 2) with mixed organic ligands of ox and en (ox = oxalate, en = ethylenediamine) have been hydrothermally synthesized and characterized by IR spectrum, thermogravimetric analysis (TGA), power X-ray diffraction (PXRD) and X-ray single-crystal diffraction, respectively. Notably, 1 and 2 are isomorphic and exhibit the first novel 2D organic–inorganic hybrid silicotungstates assembled by {Cu2Ln2(ox)(SiW11)2} dimers and [Cu(en)(ox)]/[Cu(en)2] linkers. Furthermore, the TG curve of 1 and 2 display three steps of weight loss in the range of 25–1000 °C.

Two distinct coordination polymers [Cu(Fbix)2(NO3)2]n (1) and {[Cu(Fbix)2(NO3)2]·6H2O}n (2) have been prepared from the reactions of CuII nitrate with a flexible fluorinated ligand 2,3,5,6-tetrafluoro-1,4-bis(imidazol-1-yl-methyl)benzene (Fbix) under different solvents. Single crystal X-ray diffraction reveals that 1 displays a 1-D double-chain structure containing the Fbix with gauche conformation whereas 2 has a 2-D rhombic grid network containing the Fbix with anti conformation. Their spectroscopic, thermal, and fluorescence properties have also been investigated.

A unique 3-D open coordination framework based on a fluorinated bis(imidazole) ligand has been prepared and characterized, showing a six-connected self-penetrating network with rob (48.66.8) topology. Porosity of desolvated and resolvated samples was characterized by X-ray powder diffraction (XRPD).

Four 2-D lanthanide coordination polymers constructed from 5-fluoroisophthalic acid show reliable 3-D pillared clay mimics based on the secondary hydrogen-bonding with 4,4′-bipyridine templates. The dimensionality of the structures turns out to be independent of the ionic radius of the lanthanide centers and the EuIII complex displays strong red luminescence.

Reaction of potassium N′-(pyridine-4-carbonyl)-hydrazinecarbodithioate ([K+(H2L)−]) with HgII or MnII inorganic salt in the presence of 1,10-phenanthroline (phen) or 4,4′-bipyridine (bipy), yields complexes [Hg(pyt)2(phen)] (1) and {[Mn(pyt)2(H2O)2]·(bipy)·(H2O)2}n (2), in which the pyt ligand (Hpyt = 5-(4-pyridyl)-1,3,4-oxadiazole-2-thiol) is obtained by in situ ligand formation from the acyclic precursor [K+(H2L)−]. Single crystal X-ray diffraction suggests that the pyt anionic ligands in 1 and 2 behave as thiolate and thione isomers, respectively, and display S- and μ-Npyridyl, Noxadiazole-binding fashions. Complex 1 shows a 1-D fishbone-like supramolecular array via strong aromatic stacking interactions between the discrete mononuclear coordination motifs, whereas 2 has a 2-D layered host coordination framework with the inclusion of bipy and water guests in the cavities.

Two three-dimensional (3-D) PbII coordination frameworks [Pb(BDC-F4)(CH3OH)]n (1) and [Pb(BDC-F4)(DMF)(CH3OH)]n (2) have been prepared by the reactions of Pb(NO3)2 with a rigid dicarboxyl compound tetrafluoroterephthalic acid (H2BDC-F4) in different solvents. Single crystal X-ray diffraction reveals that both complexes show the unusual rod-based coordination networks with sra topology, although they crystallize in different space groups (C2/c and P 1 ¯ ). Their spectroscopic, thermal, and fluorescence properties have also been studied.

Reaction of a flexible pyridinecarboxamide ligand N,N′-[(2,3,5,6-tetrafluoro-1,4-phenylene) bis(methylene)]bis(pyridine-4-carboxamide) (H2tfpbbp) with CuII chloride or perchlorate affords two coordination polymers {[Cu(H2tfpbbp)(tfpbbp)(H2O)] · 2DMF · 4H2O}n (1) and {[Cu(H2tfpbbp)2(ClO4)2] · 3H2O}n (2). Both complexes have 2-D (4,4) layered networks extended by the exo-bidentate bridging ligands, which however consist of distinct [Cu–ligand]4 meshes owing to the conformational difference of ligands. Their spectroscopic, thermal, and fluorescence properties have also been investigated.

A unique CdII coordination polymer {[Cd2(pyt)2(chdc)(H2O)](H2O)2}n (1) has been obtained by hydrothermal reaction and characterized by IR, microanalysis, and powder X-ray diffraction (here Hpyt = 5-(4-pyridyl)-1,3,4-oxadiazole-2-thiol and H2chdc = 1,4-cyclohexanedicarboxylic acid). Single crystal X-ray diffraction reveals that complex 1 has an unusual bilayer coordination framework with mixed-connected network topology, in which two adjacent [Cd(pyt)]n layers are spaced by chdc pillars. Thermal stability of 1 has also been discussed.