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The reaction of Ag2O and carboxylate ligands in ammonium solution results in three coordination polymers, [Ag(fbc)]n 1, [Ag2(cpd)]n 2 and [Ag2(idc)]n 3, where fbcH is 4-fluorobenzoic acid, cpdH2 is cyclopentane-1,1-dicarboxylic acid and idcH2 is iminodiacetic acid. The X-ray crystal structural analysis indicates that compounds 1 and 2 are two-dimensional frameworks and 3 is a three-dimensional framework. All the three complexes show clear Ag–Ag bonds and high cytotoxicity properties to normal cells and carcinoma cells. [Copyright &y& Elsevier]

Two compounds (NH4)2[M(dod)(H2O)4]2V10O28·6H2O (M = Zn, Mn) have been prepared in aqueous medium. X-ray single-structure analyses reveal that they are isostructural and crystallize in the triclinic space group P1. The structures of the two compounds consist of decavanadate anionic clusters and dimeric [M(dod)(H2O)4]24+ units, in which the two oxygen atoms from dod ligands ligating M2+ are in a cis fashion. There are a variety of hydrogen bonds including O–H⋯O and N–H⋯O among lattice water molecules, ammonium cations, oxygen atoms of decavanadate and oxygen atoms of dod, which extend the structures into three-dimensional supramolecular arrays. [Copyright &y& Elsevier]

Abstract: The solvothermal treatment of cobalt nitrate (or zinc acetate), ethylenediamine and dicarboxylate in acetonitrile produced two one-dimensional coordination polymers [Co(mimz)2(ox)] n (1) and [Zn(mimz)2(ip)] n (2) (mimz = 2-methylimidazoline, ox=oxalate, ip=isophthalate) which ligand involving in situ formation of imidazoline ligand by cycloaddition reaction of ethylenediamine and acetonitrile. [Copyright &y& Elsevier]

Abstract: Hydrothermal reaction of Zn/Cd salts, NaN3 and 4-cyanobenzoic acid via in situ [2+3] cycloaddition generated two blue-green photoluminescent coordination polymers [Zn(cptta)(H2O)] (1) and [Cd(cptta)(H2O)] (2) (H2cptta=5-(4′-carboxy-phenyl)tetrazole). When only metal ions are considered as nodes, 1 shows rare 5-connected Shubnikov plane topological type and 2 has unprecedented 10-connected {312.424.59} topological type. [Copyright &y& Elsevier]

Abstract: Hydrothermal treatment of cobalt chloride, 2,2′-biimidazole (H2biim), oxalate acid and NaOH at 160°C for five days produced a three-dimensional mixed-valence metal-organic framework [CoIII(Hbiim)3]2[CoII 3(ox)3]·4H2O ( 1 ). Compound 1 exhibits a 3D network with tri-nodal (3-c)2(4-c)3 topology, in which [CoIII(Hbiim)3] building blocks as 3-connected nodes, and CoII ions as 4-connected nodes. The magnetic measurements reveal that compound 1 exhibits a spin canting antiferromagnetic coupling between adjacent CoII ions. [Copyright &y& Elsevier]

Hydrothermal treatment of flexible linker 5,5′-(propane-1,3-diylbis(oxy)) diisophthalic acid (pdta) and LiOH generated a novel FL-MOF (flexible ligand based metal-organic framework) of conformational flexibility, showing gradual structural changes from 1D helical banded structure to 3D accordion-pleats-like network. Ultralight metal Li-based FL-MOF possesses hingelike movement of −O−(CH 2) 3 −O− flexible moieties on pdta linker, which resulted in large positive thermal expansion (PTE) behavior with volumetric expansion coefficient of 163.7860 MK−1. A novel accordion-pleats-like/windmill-like FL-MOF with conformational flexibility has been constructed from Li−O−Li based helical banded structure and V-shaped –−O−(CH 2) 3 −O− moiety based pdta linker, exhibiting large positive thermal expansion behaviour. Unlabelled Image • A novel Li(I)-based FL-MOF has been characterized by variable-temperature single-crystal X-ray diffraction. • The MOF performs gradual structural changes from 1D helical banded structure to 3D accordion-pleats-like network. • The MOF exhibits positive thermal expansion (PTE) with volumetric expansion coefficient of 163.7860 MK-1 • The PTE behavior was caused by the hingelike movement of −O−(CH 2) 3 −O− moieties and the short Li•••Li distance. [ABSTRACT FROM AUTHOR]

Reactions of CuCl 2 , K 2 [Ni(CN) 4 ]/K 3 [Co(CN) 6 ], and 5-amino-1H-tetrazole led to cyanide-bridged mixed-valence Cu(II/I) complexes, [Cu(H 2 O) 3 Cu 3 (CN) 5 ] ( 1 ) and [Cu(H 2 O) 4 ][Cu 4 (CN) 6 ] ( 2 ).The uncommon semi-closed {Cu 2 (CN) 3 } dimmers in 1 are bridged by μ 3 -C,C,N cyanide ligands to afford rare 1D centipedal-like chain motifs, which are further bridged by μ 2 -C,N and metalloligand “CN–Cu(4)–CN” to finish sophisticated zeolite-like 3-D structure. Topologically, 1 is the first example of uninodal 7-connected sev -like cyanide-bridged network. Compound 2 consists of two-dimensional honeycomb-related anionic layers [Cu 4 (CN) 6 ] 2 − , within which the [Cu(H 2 O) 4 ] 2 + cations are intercalated into alternate interlamellar space. Compound 1 shows antiferromagnetic couple arising from pure ground-state configuration of Cu(II) mediated by diamagnetic bridges –CN–Cu I –CN −. The inclusion compound 2 shows blue photoluminescence originated from Cu(I) center to the unoccupied π* orbital of the cyanide ligand (MLCT) charge transfer. [ABSTRACT FROM AUTHOR]

Abstract: The solvothermal reaction of CoCl2 and 2-(4-thiazolyl)-benzimidazole (Htbi) in ethanol solution at 160°C and 72h gave rise to a majority of green crystals of [Co2(Htbi)2Cl4] 1 and minor isomeric blue crystals of 2. Two isomers show quite different isolated dinuclear structures bridged by two chlorides. Complex 1 consists of edge-sharing CoN4Cl2 octahedron and CoCl4 tetrahedron, while 2 is composed of two edge-sharing CoN2Cl3 square pyramids. The intra- and inter-molecular halogen hydrogen bonds play an important role at the stabilization in the solid state. Density functional theory calculations manifest that the optimized geometric parameters match very well with the experimental ones for both isomers. The difference of calculated Gibbs free energies demonstrates that intrinsic stability of 1 is superior to 2, in agreement with their relative yields under experimental conditions. The experimental UV–vis absorption spectra in N, N-dimethyl acetamide for 1 and 2 show the same absorption bands and match the computed results. Magnetic studies of 1 reveal that strong antiferromagnetic interactions were detected between octahedral and tetrahedral Co(II) atoms. [Copyright &y& Elsevier]

Abstract: Two cuprous iodide polymorphs formulated as [N(CH3)4][Cu2I3] α and β were synthesized, in which N(CH3)4 + template that never existed in the reaction materials are in situ generated via cleavage of C N bonds and N-alkylation reactions. Solvothermal reaction of copper source, hexamethylenetetramine and HI in methanol solution at 150°C led to α and β polymorphs. Two polymorphs have been synthesized via subtle modification of the experimental condition, which indicates that the small force is also sufficient for energy difference for polymorphs. α polymorph contains one-dimensional Cu2I3 − chain in which the copper atoms are arranged into a zigzag lattice; β polymorph is composed of novel ladder-like chains which can be considered as being built up by Cu12I18 and Cu2I3 two types of secondary building units. The UV–vis absorption spectra for α and β polymorphs were investigated in reflectance mode in the solid state at room temperature, exhibiting that they belong to potential semiconductors. The excitation and emission in α and β are very distinct, which highlight that the molecular packing in polymorphs is critical to photophysical properties. [Copyright &y& Elsevier]

The antimony iodate KSbI 6 O 18 which contains cyclic S 6 -symmetric chiral hexaiodate has been successfully synthesized through hydrothermal reaction. It crystallizes in trigonal space group R-3 with cell parameters of a = 11.3057(6) Å, c = 11.3340(8) Å, γ = 120° and z = 3. Six corner-shared IO 4 groups form cyclic S 6 -symmetric chiral I 6 O 18 groups that are linked by Sb 5 + to form anionic [Sb(I 6 O 18 )] − framework with cavities filled by K + ions. Optical diffuse reflectance spectra indicate that KSbI 6 O 18 is a potential semiconductor with optical band gap of 2.96 eV. [ABSTRACT FROM AUTHOR]

Abstract: A novel 2-D organic templated bismuth–oxygen compound (H2en)0.5[BiO(OH)2(H2O)] (1) (en=ethylenediamine) has been synthesized in the presence of ethylenediamine acting as a template under mild hydrothermal conditions. The structure was determined by single crystal X-ray diffraction and further characterized by IR spectrum, elemental analysis, scanning electron microscopy (SEM), photoluminescence and thermogravimetric analysis. In the compound, the Bi atom was coordinated by eight oxygen atoms. The BiO8 polyhedra share edges or corners with their neighbors to result in an anionic inorganic layer with protonated ethylenediamine cations occupied between layers. At ambient temperature, 1 shows a blue emission band which may be assigned to the 1P1–1S0 transitions of the s2 electron of the Bi3+ ion. To our knowledge, 1 is the first example of layered bismuthate templated by an organic amine. [Copyright &y& Elsevier]

Abstract: Solvothermal treatment of silver nitrate, pyridine-4-thione (4-pdtH) and NH4SCN at 140°C for 3 days produced a three-dimensional metal–organic framework [Ag3(4-pdt)(SCN)2] (1) in which [Ag3S3] n tubes act as secondary building units and pyridine rings and CN groups act as linkers. At ambient temperature, 1 shows a blue emission band assigned as from a ligand-centred n→π∗ or π→π∗ process. [Copyright &y& Elsevier]