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Abstract High gas‐uptake capacity is desirable for many reasons such as gas storage and sequestration. Moreover, ultrahigh capacity can enable a practical separation process by mitigating the selectivity factor that sometimes compromises separation efficiency. Herein, a single‐walled nickel–organic framework with an exceptionally high gas capture capability is reported. For example, C2H4 and C2H6 uptake capacities are at record‐setting levels of 224 and 289 cm3 g−1 at 273 K and 1 bar (169 and 110 cm3 g−1 at 298 K and 1 bar), respectively. Such ultrahigh capacities for both gases give rise to an excellent separation performance, as shown for C2H6/C2H4 with breakthrough times of 100, 60 and 30 min at 273, 283 and 298 K and under 1 atm. This new material is also shown to readily remove ethylene released from fruits, and once again, its ultrahigh capacity plays a key role in the extraordinary length of time achieved in the preservation of the fruit freshness.

The article explains the synthesis and characterization of a new family of penta- and tera-manganese(III) complexes, which are usually derived from an assembly system containing tert-butylphosphonic acid. The structures of the N-containing donors are shown to highly affect the structures of these compounds.

The synthesis and characterization of various 3D porous cobalt-organic frameworks are studied. These compounds are shown to exhibit spin-canted antiferromagnetism and field-induced spin-flop transition.

The structural analysis of a hydrothermally synthesized a polyoxometalate with hybrid hexanuclear copper cluster is carried out. The spatial arrangement and magnetic properties of all the units are discussed.

Systematic syntheses, structures, visible luminescence and magnetic properties of a series of new lanthanide hybrids are described. The structures contain trigonal dodecahedral chains and clustered lanthanide oxide ring tunnels and 3D Ln-O-Ln connectivity.

The two novel high-symmetry 3D porous frameworks of cadmium tetrazolate [[Cd.sub.5[(tetrazolate).sub.9](OH)([H.sub.2]O].sub.n].5n[H.sub.2]O and [[Cd.sub.5[(aminotetrazolate).sub.9][N[O.sub.3]]].sub.n].3n[H.sub.2]O are developed under hydrothermal conditions. It is revealed that their structures are haracteristic of hexagonal tunnels through the trigonal-prismatic and hexagonal tubelike building units and exhibit their high stabilities of porous frameworks against the removal of the guest molecule.

Solvothermal reaction of Cu(OAc)2·H2O, tri(2-carboxyethyl)isocyanurate (H3tci) and 4,4′-bipyridine (bpy) or 1,3-bis(4-pyridyl)propane (bpp) leads to the generation of two novel metal–organic frameworks, [Cu(Htci)(bpy)]·0.5H2O (1) and [Cu3(tci)2(bpp)2(H2O)]·3H2O (2). 1features a 3D self-penetrating framework which results from two-fold interpenetrating 4-connected CdSO4nets linked by carboxylate oxygen atoms of tci ligands. 2is a 3D self-penetrating 3,4,6-connected 3-nodal net with the stoichiometry (3-c)2(4-c)(6-c) constructed by a two-fold interpenetrating (4.102)2(42.104) net connected by bpp ligands. [ABSTRACT FROM AUTHOR]

The use of phosphonic acids in the synthesis of mixed-metal CeMn complexes has led to the formation of two phosphonate complexes with unusual topologies: [Ce2Mn6O6(OH)5(t-BuPO3)6(O2CMe)3]·53H2O (1·53H2O) and [Ce22Mn12O34(MePO3)12(O2CMe)33(OMe)6(NO3)(H2O)12]n(2). The two mixed-metal CeMn complexes were both prepared from a reaction system containing Mn(O2CMe)2and (NH4)2[Ce(NO3)6] with similar procedures except for using different phosphonic acids (tert-butylphosphonic acid and methylphosphonic acid, respectively) as coligands. Both complexes possess rare topology of triangular type, with compound 1being a 0D discrete cluster, whereas, compound 2is a 1D polymer. The octanuclear core of complex 1is composed of three symmetry equivalent distorted cubanes {CeIV2MnIV2O2(OH)2} sharing a trigonal-bipyramidal unit {CeIV2(OH)3} in the centre. Compound 2is a one-dimensional chain polymer of identical Ce22Mn12O34units linked together by NO3−and MeCO2−groups, while the Ce22Mn12O34unit is constituted by two centrosymmetric Ce9IVCe2IIIMnIV6O17subunits, which features three identical distorted cubanes {CeIV2MnIV2O4} connecting to a central trigonal-bipyramidal unit {CeIV3O2}, and two additional CeIIIions capping the top and bottom of the central trigonal bipyramid by six MePO32−ligands. Complexes 1and 2are the first high-nuclearity Mn/Ln aggregates reported to date using phosphonates as ligands. Magnetic susceptibility measurements reveal that compound 1displays dominant ferromagnetic interactions between the adjacent metal ions with the best fit parameters for the exchanges are J1= 6.186 cm−1, J2= 4.172 cm−1, and with a result of S= 9 ground state confirmed by the M versus HT−1data, which indicates the spins of all the six MnIVions in the cluster are parallel to each other. In contrast, the data for 2reveals overall antiferromagnetic couplings within the cluster and a resulting S= 6 ground state. Both the in-phase signal χ′MTand out-of-phase signal χ′′Mof the two complexes exhibit frequency-dependent below approximate 3 K. [ABSTRACT FROM AUTHOR]

Five indium(iii) compounds with 2,5-pyridine dicarboxylate ligands: {[4,4′-Hbipy] [In(Hpdc)(H2O)Cl3]·2H2O}n(1), {[4,4′-H2bipy]4[In2(pdc)7(H2O)]·7H2O}n(2), {[4,4′-H2bipy]3[In2(pdc)6(H2O)]·6H2O}n(3), {[In2(pdc)2(bpno)(H2O)2Cl2]·2H2O}n(4) and [In2(pdc)2(2,2′-bipy)Cl2]n(5), (H2pdc = 2,5-pyridine-dicarboxylic acid, 4,4′-bipy = 4,4′-bipyridine, bpno = 4,4′-bipyridine N,N-dioxide, 2,2′-bipy = 2,2′-bipyridine) were hydrothermally or solvothermally synthesized and their structures were determined by X-ray single-crystal diffraction. Compounds 1and 2are both mononuclear structures, which are assembled into 3-D supramolecular structures by various hydrogen bonding; compound 3consists of two types of infinite 1-D indium(iii)-carboxylate chains; compound 4is a 2-D wave-like plane structure formed by bpno linked indium(iii)-carboxylate chains. An unprecedented 3-D chiral framework of compound 5with three kinds of helices along [010] direction is observed, considering that the construction of a chiral structure by rigid achiral ligands is rare. A topological analysis using TOPOS4.0 indicates that compound 5is a unique and novel example of self-penetrated (4,8)-connected binodal lattice with a {32.64}{34.44.58.69.72.8} Schläfli symbol. The above-mentioned compounds were also characterized by X-ray powder diffraction (XRD), thermal gravity analysis (TGA) and photoluminescent studies. [ABSTRACT FROM AUTHOR]

Two 3D cobalt—organic frameworks formulated as [Co3(2,4-pydc)2(μ3-OH)2]n·5nH2O (1) and [Co3(2,4-pydc)2(μ3-OH)2(H2O)]n·7nH2O (2) (2,4-pydc = pyridine-2,4-dicarboxylate) have been hydrothermally synthesized and characterized. Both compounds 1 and 2 exhibit the 3D porous frameworks with hydroxyl-bridged metal Δ-chains. However, in comparison with only two crystallographically independent CoII ions in a unit of 2, three crystallographically independent CoII ions are found in an asymmetric unit of 1, where their Δ-chains are constructed by two types of vertexes sharing quadrangles formed via edge-sharing triangles. Magnetic studies show that 1 exhibits spin-canted antiferomagnetism and a field-induced spin-flop transition while 2 behaves as a normal antiferromagnet. The magnetic properties are largely retained by the porous frameworks of dehydrated 1 and 2 compounds. Gas adsorption measurements indicate that both the dehydrated compounds absorb H2 into their pores. [ABSTRACT FROM AUTHOR]

Hydrothermal synthesis of a series of copper(II)−H3SIP coordination polymers (H3SIP 5-sulfoisophthalic acid), Cu3(SIP)2(H2O)14(1), Cu(SIP)(H2O)4(H2en)0.5n(2), NaCu2(SIP)(HSIP)(H2O)8(H2O)3n(3), Cu4(OH)2(SIP)2(H2O)2(H2O)4n(4), Cu2(OH)(SIP)(bpy)(H2O)n(5), Cu4(OH)2(SIP)2(bpy)3(H2O)n(6), and Cu4(OH)2(SIP)2(bpy)2(H2O)2n(7) (bpy 2,2‘-bipyridine; en ethylenediamine), has been achieved by fine control over the reaction conditions including pH value, organic template, reaction temperature, starting materials, auxiliary ligand, and stoichiometry. X-ray structural analyses of 1−7reveal their structural diversity ranging from zero-dimensional (0-D) (1), one-dimensional (1-D) (2), two-dimensional (2-D) (3, 5, and 6), to three-dimensional (3-D) (4and 7). The relationship between the reaction conditions and the resulting structures has been rationalized. The trinuclear complex 1represents the first example of a discrete metal−SIP coordination complex. The presence of countercations such as H2en2and Naleads to the formation of a Cu−SIP zigzag chain in 2and 3. A larger template such as triethylenediamine (TEDA) accounts for the formation of the tetranuclear Cu4(3-OH)2secondary building unit (SBU) in 4and hence the 3-D network structure with unprecedented (411·614·83)(45·6)2topology. Polymer 5formed at a comparatively lower temperature has the binuclear Cu2(2-OH) SBU and thus the 2-D double-sided layer structure of 4·82topology. The enhanced temperature results in the formation of the tetranuclear Cu4(3-OH)2SBU of 7and hence the 3-D framework structure of rutile topology (4·62)2(42·610·83). 6contains the unusual tetranuclear Cu4(3-OH)(2-OH) SBU induced by one more bpy ligand that results in a 2-D layered structure of unique (3·52)2(32·53) topology. The temperature-dependent magnetic susceptibility data of 1−5have been modeled using both Curie−Weiss law and isotropic spin-Hamiltonian, revealing weakly ferromagnetically or antiferromagnetically magnetic interactions between the Cu2ions bridged by OH-or SIP ligands. [ABSTRACT FROM AUTHOR]

A novel sandwich-type polyoxometalate incorporating a unique hybrid hexanuclear copper cluster, [Cu(enMe)2]2- {[Cu(enMe)2(H2O)]2[Cu6(enMe)2(B-a-SiW9O34)2]}·4H2O (1, enMe = 1,2-diaminopropane), has been hydrothermally synthesized and structurally characterized by the elemental analyses, IR spectroscopy, TG analysis, magnetic properties, and single-crystal X-ray diffraction analysis. Crystal data for 1: triclinic, P1; a = 12.5105(2), b = 14.3710(2), c = 17.2687(2) Å; α = 98.834(1), β = 110.744(1), γ = 104.711(1)°; V = 2704.57(7) ų; ρ = 3.646 g/cm³ Z = 1. X-ray crystallographic study shows that the molecular structure of 1 contains 10 copper ions: Six of them form an unprecedented inorganic-organic hybrid Cu6 cluster via edge-sharing combination of two CuO6 octahedra, two CuO5, and two CuO3N2 square pyramids and are encapsulated between two {B-a-SiW9O34} units. Two of them form two [Cu(enMe)2(H2O)]2+ complexes and further attach to the two {B-a-SiW9O34} units via two Cu-OW bridges, acting as a decorated role. The remaining two form isolated [Cu(enMe)2]2+ complexes playing roles of charge-compensation and space-fillers. Magnetization measurement reveals that the hexanuclear copper cluster exhibits overall ferromagnetic interactions. [ABSTRACT FROM AUTHOR]