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With the help of the ligand-oriented method, we have successfully embedded independent copper-based units into the indium-organic framework system for the first time, in which the Cu4I4 clusters and In3O(CO2)6 clusters coexist. This heterometallic cluster-based framework InOF-8 has a large porosity with extra-open channels along the c-axis, and its sorption capacity has also been investigated. [ABSTRACT FROM AUTHOR]

Two indium--organic framework isomers, namely [Me2NH2][In(BPDC)2](InOF-3)and[MeNH3][In(BPDC)2] (InOF-4), have been solvothermally prepared from a biphenyl-3,3'-dicarboxylate ligand (H2BPDC) with changeable conformation, and feature skeletal frameworks with equivalent chemical formulae. For the 2D close-packing InOF-3, each 3-connected [In(O2CR)4] node connects to 3 others through syn-BPDC² ligands, leading to a 3-connected uninodal layer with a point symbol of {6³}. For the 3D microporous InOF-4, the framework is assembled from [In(O2CR)4] nodes bridged by dicarboxylate ligands in the anti- fashion. Careful examination of the structure shows that InOF-4 is a 4-fold interpenetrating network and topologically adopts a diamond-like 4-connected uninodal net with a point symbol of {66}. More importantly, the theoretical calculations and the experimental single component gas uptake measurements reveal that the 3D porous InOF-4 has a better low pressure gas storage capacity than its 2D framework isomer InOF-3, with a saturated N2 uptake of 168.2 cm³ g at 77 K and H2 uptake capacities of up to 126.5 cm³ g-1 (1.13 wt%) at 77 K and 1.0 bar, and 98.1 cm³ g-1 (0.88 wt%) at 87 K and 1.0 bar. Finally, the IAST calculations show us that both microporous materials have an outstanding low-pressure selectivity between CO2 and N2, probably due to their intrinsic structural characteristics. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), also known as coordination polymers (CPs), are crystalline materials constructed from metal ions or clusters bridged by organic ligands to form one-, two-, or three-dimensional infinite networks. In contrast with the prolific production of MOFs based on rigid ligands (RL-MOFs), the design, syntheses and applications of MOFs based on flexible ligands (FL-MOFs) are somewhat overlooked. Although sacrificing a measure of control, the use of flexible ligands may provide unique opportunities to obtain novel crystalline framework materials exhibiting desirable attributes. In this review, emphasis has been placed on the design and the structural diversity of FL-MOFs. Homochiral FL-MOFs and dynamic frameworks induced by flexible ligands are also briefly outlined. An overview is also shown for the applications of FL-MOFs as platforms for gas adsorption, heterogeneous catalysis, proton conduction etc. [ABSTRACT FROM AUTHOR]

Self-assembly of Co(II)/Cd(II) with 4,4'-sulfonyldibenzoic acid and bis(4-pyridylmethyl)piperazine has produced 3D interpenetrated and non-interpenetrated polythreading networks with non-trivial linkages. [ABSTRACT FROM AUTHOR]

A novel third-order nonlinear optical (NLO) crystal based on the organic borate carboxylate ester, with formula [Na4(H2O)5][B{O2CCH(O)Ph}2]4(abbreviated as LMBNa), has been prepared in aqueous solution. Single-crystal X-ray diffraction analysis reveals that the boron atom is coordinated with two l-mandelic ligands by alkoxide and carboxylate groups, forming the [B{OOCCH(O)C6H5}]−anion. The sodium cation supports its structural framework of borate anions in the formation of a cross-linked structure. Bulk single crystals of LMBNa were grown from acetonitrile/water by the temperature lowering method. Studies of its third-order NLO properties using a Z-scan technique demonstrate that the LMBNa crystal possesses a strong saturable absorption and the self-focusing effect. Its second molecular hyperpolarizability (γ) at 532 nm is calculated to be (3.9 ± 0.2) × 10−31esu. Furthermore, dielectric experiments reveal that LMBNa has a quite low-dielectric constant (∼3.43) and shows an anisotropy of frequency dependence along the different crystallographic directions. Such dielectric behaviors will favor the application of the LMBNa crystal under the electric field. All the results indicate that LMBNa might be a potential candidate material for the third-order NLO applications. [ABSTRACT FROM AUTHOR]

Two three-dimensional coordination polymers were solvothermally prepared through in situformation of a 2-sulfobenzoic acid ligand from a 2,2′-dithiobisbenzoic acid precursor involving the oxidative cleavage of its disulfide bond. Complex 1shows neb-e topology, while complex 2exhibits a scarcely reported twisting chiral dense 75.9 net. [ABSTRACT FROM AUTHOR]

Four novel lanthanide(iii)–copper(ii) heterometallic coordination polymers based on six-coordinated Cu centres and square-planar tetranuclear {Ln4} SBUs with sulfate as an auxiliary bridging ligand, namely, [Ln2Cu0.5(2,6-pydc)2(2-pyc)(SO4)(H2O)2]·(H2O) (Ln = Nd 1, Sm 2, Eu 3, Gd 4; 2,6-pydc = pyridine-2,6-dicarboxylate, 2-pyc = pyridine-2-carboxylate), have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Compounds 1–4are isostructural and present a rarely reported binodal (4,6)-connected fscnet with the Cu centre as a four-connected node and the tetranuclear {Ln4} SBUs as six-connected nodes. As far as we know, a fscnet in hetero-Ln–TM coordination polymers has never been reported. This work provides a good example of incorporating {Ln4} SBUs and Cu centres to construct a heterometallic binodal net. Notably, the 2-pyc ligand was in situgenerated by decarboxylation of the 2,6-pydc ligand under hydrothermal conditions. Furthermore, the IR, TGA, PXRD, luminescent and magnetic properties were also investigated. [ABSTRACT FROM AUTHOR]

Details the preparation of the polymeric silver(I) thiolate ligands from the controlled assembling reactions of silver chloride and 2-mercaptopyridine. X-ray diffraction and analysis; One-dimensional chain structure; Three-dimensional network structure; Coordination geometry; Sulfur atom of the thiolate ligand.

Ligands with flexible conformations add to the structural diversity of metal-organic frameworks but, at the same time, pose a challenge to structural design and prediction. Representative examples include Zr-tetracarbox-ylate-based MOFs, which afford assorted structures for a wide range of applications, but also complicate the structural control. Herein, we systematically studied the formation mechanism of a series of (4,8)-connected Zr-tetracarbox-ylate-based MOFs by altering the substituents on different positions of the organic linkers. Different ligand rotamers give rise to three types of structures with flu, scu, and csq topologies. A combination of experiment and molecular simulation indicate that the steric hindrance of the substituents at different positions dictates the resulting MOF structures. Additionally, the controllable formation of different structures was successfully implemented by a combination of linkers with different steric effects at specific positions. [ABSTRACT FROM AUTHOR]

A novel tripodal ligand L that only has a syn conformer has been designed and synthesized. Different Ag3L2 metallocages can be effectively assembled from such concave ligands and different Ag(I) salts. ESI-MS research indicates that a Ag3L2 metallocage can encapsulate different anions selectively, in which the encapsulation capacity is as follows: NO3- > ClO4- > SO42-; moreover, selective encapsulation of NO3- from a mixture of NO3- and ClO4- has been observed. [ABSTRACT FROM AUTHOR]

Herein, 15 lanthanide coordination complexes based on three di-, tri-, and tetra-carboxylic ligands with imidazolyl groups have been solvothermally designed, synthesized, and characterized. All the complexes exhibit high thermal stabilities and can remain stable in the open air more than 7 days. Luminescent spectra of Eu3+ and Tb3+ complexes at room temperature indicate that the three carboxylic ligands H2L¹, H3L², and H4L³ are promising potential light sensitizers for lanthanide ions based on their suitable triplet energy levels. Luminescent lifetimes and quantum yields of these compounds were further measured and compared. The correlations between their structural features and photophysical properties are discussed in detail. [ABSTRACT FROM AUTHOR]

Utilizing presynthesized large Na2Ni12Ln2 clusters (Ln = Dy and Tb) supported by calixarene as molecular building blocks (MBBs), we have obtained a series of cationic trigonal prismatic heterometallic organic nanocages (HMONCs) with tunable sizes through a stepwise method. Specially, in each structure of the HMONCs, three linear dicarboxylate linkers substitute the peripheral coordinated acetate ligands of two Na2Ni12Ln2 clusters to form an unprecedented Na4Ni24Ln4 HMONC through a M2L3 condensation. Moreover, magnetic study reveals that the Na2Ni12Dy2 core retains its slow magnetic relaxation behavior. Gas sorption behaviors of these HMONCs were also studied. To the best of our knowledge, these HMONCs built from large heterotrimetallic Na2Ni12Ln2 MBBs, which are based on smaller Ni4-calix ones, have not been reported in any other cages to date. In addition, this research also provides a new strategy for the design and construction of HMONCs with predictable structures and functional properties. [ABSTRACT FROM AUTHOR]

A microporous metal organic framework structure, Zn2(bpdc)2(bpee)—2DMF (DMF; N, N-dimethylformamide), has been synthesized via solvothermal reactions. The compound is a new member of the RPM series (RPM=Rutgers Recyclable Porous Material) that possesses a flexible and recyclable three-dimensional framework containing one-dimensional channels. It exhibits interesting and multifold functionality, including porosity, commensurate absorption for hydrocarbons, high hydrogen binding energy (determined by isosteric heats of hydrogen adsorption and confirmed by van der waals density functional calculations) as a result of multifold binding to aromatic ligands (determined by IR spectroscopy), strong photoluminescence emission, and reversible flourescence quenching properties. [ABSTRACT FROM AUTHOR]

A enneanuclear nanocage, [Ni9(HL)6(Pz)6](PzH)3(ClO4)3(H2O)24(1), has been synthesized by coordination-driven face-directed self-assembly of octahedral Ni(II) ions and asymmetric hydrazone ligands with addition of pyrazole in ethanol solution. Compound 1with hexahedral nanocage structure has been characterized by elemental analysis, FT-IR, TGA, ESI-MS, and X-ray diffraction analysis. Furthermore, variable-temperature magnetic studies for compound 1have also been reported. [ABSTRACT FROM AUTHOR]

Five new d 8and d 10metal complexes, Pd(8-hq) 2( 1), [Ag(8-Hhq) 2]NO 3( 2), Ag(8-hq)(8-Hhq) ( 3), [(8-H 2hq) 2PdCl 4]·2H 2O ( 4), and Pt(8-hq)(tht)Cl ( 5) (tht = tetrahydrothiophene), all with a fluorogenic chelating agent, 8-hydroxyquinaldine (8-Hhq), have been synthesized and characterized. The aggregations of their photoactive metal centers through π−π stacking and hydrogen bonding interactions construct the interesting frameworks. The strong emissions of 1− 3and 5in solid states with orange, cyan, and green luminescences originating from metal··· metal and π−π interactions are assigned as metal to ligand charge transfer/metal–metal to ligand charge transfer/intraligand emissions. The solvent effects on their photophysical properties are examined, which exhibit a wide range of strong luminescences in the different organic solvents. In addition, time-dependent density functional theory calculations using the B3LYP functional on 1are in good agreement with the experiments. Thermogravimetric analyses and UV/vis spectra with composition of certain simulated results are also reported. [ABSTRACT FROM AUTHOR]

A porous polyhedral metal-organic framework has been constructed by utilizing Zn2(COO)4and Zn2(COO)3SBUs as nodes and the flexible hexacarboxylate as linkers. The framework contains four types of interconnected polyhedral cages, rhombic dodecahedron, tetrahedron, octahedron, and distorted tetragonal prism. To identify the topology of the whole network, the four types of polyhedral cages can be viewed as nodes, and the whole network is signed as a (6,6,12,12) network. In another view of point, the Zn2(COO)3SBU, Zn2(COO)4SBU and hexacarboxylate ligands can also be considered as nodes, then the network is simply signed as a (3,4,6)-connected net with a Schläfli symbol (43) (4462) (4679). [ABSTRACT FROM AUTHOR]