Assembling hierarchical metal–oxygen building units with a semirigid tetracarboxylate ligand into a three-dimensional framework for nitrobenzene sensing

A three-dimensional framework collecting hierarchical metal–oxygen multicluster, macrocyclic, and infinite chain-like building units was fabricated and investigated as efficient luminescent sensor towards nitrobenzene.

Structures of Metal-Organic Frameworks with Rod Secondary Building Units

Rod MOFs are metal-organic frameworks in which the metal-containing secondary building units consist of infinite rods of linked metal-centered polyhedra. For such materials, we identify the points of extension, often atoms, which define the interface between the organic and inorganic components of the structure. The pattern of points of extension defines a shape such as a helix, ladder, helical ribbon, or cylinder tiling. The linkage of these shapes into a three-dimensional framework in turn defines a net characteristic of the original structure. Some scores of rod MOF structures are illustrated and deconstructed into their underlying nets in this way. Crystallographic data for all nets in their maximum symmetry embeddings are provided.

Syntheses, structures and luminescence of a series of coordination polymers constructed with 4-substituted 1,2,4-triazole and biscarboxylate co-ligands

Eight coordination polymers were hydrothermal synthesized based on semi-rigid 4-substituted 1,2,4-triazole btpm and biscarboxylate ligands. 1–8 show the structural diversity based on mono-metal, bi-, tri- and tetra-nuclear metal clusters.

A Novel (3,4,9)-Connected 3D Metal–Organic Framework Based on the Non-Planar Tricarboxyl Tecton and Zn5O4-Cluster SBU

Combination of a non-planar tripodal ligand 3,4-bi(4-carboxyphenyl)-benzoic acid (H3L) and Zn5O4-cluster secondary building units affords a highly connected three-dimensional metal–organic framework, {[Zn5(μ3-OH)3(μ2-OH)L2(H2O)2](H2O)2}n (1), which exhibits an unusual (3,4,9)-connected (42.5)(3.43.52)(32.45.511.613.73.82) topological net. The thermal stability and solid luminescence of the crystalline material have also been investigated.

A series of novel zinc(II) entangled coordination polymers based on carboxyphenyl-terpyridine ligands

Hydrothermal synthesis has afforded five divalent zinc coordination polymers containing 4-(4-carboxyphenyl)-2,2':6',2''-terpyridine (HL1) or its isomer 4-(4-carboxyphenyl)-2,2':4',4''-terpyridine (HL2), with or without the addition of auxiliary ligands, 1,3,5-benzenetricarboxylic acid (H3btc) and 1,4-benzenedicarboxylic acid (H2bdc). Their structures have been characterized by single crystal X-ray analyses and further characterized by infrared spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses and photoluminescent spectra. Across this series, the π···π interactions have a dramatic impact on the self-assembly of these entanglement structures, in either case it can exert an important structure-directing role. In addition, the disposition of pyridine nitrogen atoms in ligands also plays a large role in structure direction in this system. Complex 1 is a 2D + 2D→3D inclined polycatenated coordination polymer based on the resulting array of 2D (6,3) layers constructed by 1D→2D π···π directed self-assembly. Complex 2 is assembled into a 3D framework by means of 1D + 1D→3D mutual interdigitation based on 1D→1D self-assembly driven by π···π stacking interactions. Complex 3 shows a 2D + 2D→3D interdigital network involving 2D + 2D→2D parallel interpenetrated and 2D + 2D→2D interdigital (4,4) layer motifs. Complex 4 displays a 2D + 2D→3D polythreaded framework based on a 2D (4,4) network comprised of alternating rings and rods. Complex 5 is a (3,4)-connected 3D framework with topology (4.8(2).10(3))(4.8(2)). In comparison with covalently connected entanglements, such π···π directing self-assembly of entanglements are far less explored, especially, polycatenane based on 1D chain motifs and polythread based on 2D layer motifs are rarely reported. Furthermore, the luminescent properties of complexes 1-5 at room temperature have also been studied in detail herein.