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Two novel hybrid materials based on two kinds of octamolybdate anions and metal–organic frameworks (MOFs), namely, [Ag8(L1)4(α-Mo8O26)(β-Mo8O26)(H2O)3]·H2O (1) and [CuI3.1CuII0.5(β-Mo8O26)0.5(ζ-Mo7VIMoVO26)0.5(L2)2(H0.8L2)0.5] (2), where L1= 1,1′-(1,3-propanediyl)bis[2-(4-pyridyl)benzimidazole] and L2= 1,1′-(1,4-butanediyl)bis[2-(3-pyridyl)benzimidazole], have been successfully synthesized. Crystal structure analysis revealed that 1is a three-dimensional (3D) framework constructed of silver(i)–organic sheets and two types of (Mo8O26)4−isomers. Compound 2is a rare 3D framework containing copper(i,ii)–organic cages and 1D channels occupied by the (ζ-Mo7VIMoVO26)5−and (β-Mo8O26)4−anions. The two compounds were characterized by elemental analysis, IR spectroscopy, diffuse reflectivity spectroscopy, and photoluminescent spectroscopy. In addition, the photocatalytic behavior of 1was investigated. [ABSTRACT FROM AUTHOR]

Two novel Cu(II) compounds [Cu2(btb)3.5(C4AS)(H2O)]·2.5(H2O) (1) and [Cu2.5(btp)2(C4AS)(htz)(H2O)3]·4.75(H2O) (2) have been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction analyses (btb = 1,4-bis(1,2,4-triazol-1-yl)butane, btp = 1,5-bis(1,3,4-triazol-1-yl)pentane, htz = 1,3,4-triazolate, and C4AS = p-sulfonato-calix[4]arene). In 1, the btb ligands connect Cu(II) atoms to form a 3D porous framework. The 1D chains constructed by C4AS and Cu(II) atoms are further bonded to the 3D porous framework through the Cu–O bonds. Topologically, structure 1belongs to a 3D (3,6)-connected net with the Schläfli symbol of (42·6)(46·68·8). In 2, the C4AS links the Cu(II) atoms to form 1D chains, which are further connected by the btp and htz to generate a 3D (3,4,6)-connected framework with the Schläfli symbol of (62·8)(52·62·7·8)(54·62·7·87·9). The two compounds have been further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), thermogravimetric (TG) analyses, and UV–vis absorption spectra. [ABSTRACT FROM AUTHOR]

In this article, five new silver(i) coordination polymers constructed from tetrakis(imidazol-1-ylmethyl)methane (L) and various anions have been synthesized, namely, [Ag(L)0.5](NO3)·0.5(H2O) (1), [Ag(L)0.25Br] (2), [Ag2L](mal)·6.25H2O (3), [Ag2L(1,3-bdc)]·4H2O (4), and [Ag2L(1,4-bdc)0.5]·0.5(1,4-bdc)·7.5H2O (5), where H2mal = maleic acid, 1,3-H2bdc = benzene-1,3-dicarboxylic acid, and 1,4-H2bdc = benzene-1,4-dicarboxylic acid. In compound 1, Ag(i) atoms are connected by the L ligands to form a 2D 4-connected square layer (sql) with free NO3−anions in the channels. The resulting layers are extended into 3D supramolecular frameworks through π–π interactions. In compound 2, the L ligands link the Ag4Br4cluster to form a two-fold interpenetrating diamond (dia) architecture. When the dicarboxylate ligands H2mal, 1,3-H2bdc and 1,4-H2bdc were used in the reaction, compounds 3–5were obtained. In compound 3, the Ag(i) atoms are bridged by the L ligands to furnish a 3D trinodal (3,4)-connected (62·8)(4·6·8)(4·62·82·10) net with the mal ligands just as free counteranions. In compound 4, the 1,3-bdc ligand coordinates to the Ag(i) center in a monodentate mode. The L ligands link the Ag(i) atoms to form a 2D double layer structure with point symbol (62·8)2(64.82). In compound 5, the L and 1,4-bdc ligands connect the Ag(i) atoms to form a complicated 3D (3,4)-connected framework with point symbol (4·102)2(42·6)2(42·103·12)(42·6·103)2. The influence of the anions on the structures of the coordination polymers has been discussed. Additionally, the luminescent properties of these compounds were also studied. [ABSTRACT FROM AUTHOR]

A series of structurally diverse metal–organic frameworks (MOFs), [Co4(TPOM)2(L1)4(H2O)4]·H2O (1), [Ni2(TPOM)(L2)2(H2O)2]·2H2O (2), [Co2(TPOM)(L2)2(H2O)2]·H2O (3), [Cu4(TPOM)2(L3)4]·3H2O (4), [Co2(TPOM)0.5(L4)] (5), and [Cd(TPOM)(L3)3]·7H2O (6), where TPOM = tetrakis(4-pyridyloxymethylene)methane, H2L1 = 1,3-benzenedicarboxylic acid, H2L2 = 5-hydroxyisophthalic acid, H3L3 = 1,3,5-benzenetricarboxylic acid, and H4L4 = 1,2,4,5-benzenetetracarboxylic acid, have been hydrothermally synthesized. These complexes were structurally characterized by X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Compound 1shows a 3D 4-connected framework with a rare (84·62) topology. Compounds 2and 3are isostructural and display 3D 2-fold interpenetrating frameworks with (64·82)(66)2topologies. Compound 4exhibits a 2-fold interpenetrating structure with a scarce trinodal (3,4,5)-connected (4·62)(4·69)66topology. Compound 5possesses a 3D 4-connected net with the TPOM ligands located in the 3D channels. Compound 6features 2D square layers (sql). The free TPOM ligands and L3 anions form discrete fragments through hydrogen bonds and π–π interactions. Interestingly, the fragments penetrate the 2D networks above and below to yield a unique 2D → 3D polythreading framework. The structural differences among such compounds show the effects of the carboxylates and central metals on the complex structures. The UV–vis absorption spectra, optical energy gap, and luminescent properties were also investigated for the compounds. [ABSTRACT FROM AUTHOR]

Thirteen new metal–organic frameworks (MOFs), namely, [Zn2(L1)2(biim-4)(H2O)] (1), [Cd(HL1)2(biim-4)] (2), [Cd(HL2)2(biim-4)] (3), [Cd(HL3)2(biim-4)] (4), [Zn2(L4)2(biim-4)(H2O)] (5), [Cd(HL4)2(biim-4)] (6), [Zn2(L5)2(biim-4)(H2O)] (7), [Cd(HL5)2(biim-4)1.5]·H2O (8), [Zn2(L6)2(biim-4)(H2O)] (9), [Cd(HL6)2(biim-4)] (10), [Zn2(L7)2(biim-4)2]·H2O (11), [Cd2(L7)2(biim-4)2(H2O)]·H2O (12), and [Zn(HL8)(biim-4)]·0.5H2O (13), where H2L1 = salicylic acid, H2L2 = 3-methylsalicylic acid, H2L3 = 4-methylsalicylic acid, H2L4 = 4-chlorosalicylic acid, H2L5 = 5-chlorosalicylic acid, H2L6 = 5-bromosalicylic acid, H2L7 = 5-nitrosalicylic acid, H3L8 = 5-sulfosalicylic acid, and biim-4 = 1,1′-(1,4-butanediyl)bis(imidazole), have been synthesized under hydrothermal conditions. Compounds 1and 5are isomorphous, and show the same 3-connected 103-thsnet. Compound 2possesses a meso-helical chain structure. Compound 3shows a zero-dimensional (0D) dimeric molecular structure, which is linked by π–π interactions into a two-dimensional (2D) supramolecular assembly. Compounds 4and 6exhibit similar one-dimensional (1D) chains, which are extended into different 2D supramolecular layers via C–H···O and C–H···Cl hydrogen-bonding interactions, respectively. Compound 9is isomorphous with 7and displays a typical 3D diamond framework. Compound 8shows an unusual 2D → 3D polythreading array. Compound 10furnishes a 2D supramolecular (44)-sqlnetwork formed by C–H···Br hydrogen-bonding interactions. Compounds 11and 12exhibit binodal (4,4)-connected 3D frameworks with (4.53.72)(4.52.83) and (42.62.82)(42.6.82.10) topologies, respectively. Compound 13has a 3D 4-fold interpenetrating diamond framework. The TGA and luminescent properties of 1–13have also been investigated in detail. [ABSTRACT FROM AUTHOR]

Four octamolybdate hybrid materials based on a new flexible multidentate ligand, namely, H4L(γ-Mo8O26)·2H2O (1), [Cu(H2L)(β-Mo8O26)(H2O)2]·3H2O (2), [Cu(H2L)(γ-Mo8O26)]·3H2O (3), and Cu(HL)2(β-Mo8O26) (4), where Lis 1,1′-(1,4-butanediyl)bis[2-(4-pyridyl)benzimidazole], have been synthesized at different pH values under hydrothermal conditions. Compound 1, which is hydrothermally prepared at pH ≈ 1, exhibits a rare one-dimensional (1D) molybdenum oxide chain. Compounds 2and 3are hydrothermally obtained at pH ≈ 2.5. In 2, CuIIcations are bridged by H2L2阨᪝ and (β-Mo8O26)4–anions to form an interesting two-dimensional (2D) layer. In 3, the H2L2阨᪝ and (γ-Mo8O26)4–clusters bridge adjacent CuIIcations to form a 3D framwork. When the pH value is adjusted to 3.5, compound 4is obtained. Because the HL熫抢 acts as a monodentate ligand, compound 4only exhibits a 1D chain structure. The structural diversities of 1–4reveal that the pH value of the reaction system plays a crucial role in the assembly of POM-based metal–organic frameworks (MOFs). In addition, the electrochemical property of compound 4has also been investigated in 1 M H2SO4aqueous solution. [ABSTRACT FROM AUTHOR]