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Highlights: [•] Two novel d10 metal polymers based on tetrazole-1-acetic acid ligand were obtained. [•] The flexibilities of 1-tza ligand result in 1-D helical chain of the two complexes. [•] Photoluminescence studies show that the two complexes exhibit strong luminescence. [•] The Zn(II) tetrazolate-1-acetic acid complex, [Zn(1-tza)(Cl)(H2O)] (1), displays nonlinear optical effect. [ABSTRACT FROM AUTHOR]

Abstract: Two 3D metal-organic supramolecular complexes [Zn2(btec)(2, 2′-bpy)2(H2O)2] (1), [Cd2(dpa)2(phen)2(H2O)2] (2) have been prepared by hydrothermal reaction and characterized by IR and single-crystal X-ray diffraction analysis. The 3D architectures of 1 and 2 both possess rectangular cavities. Furthermore, compounds 1 and 2 both show intense photoluminescent properties at room temperature. [Copyright &y& Elsevier]

Abstract: A new compound, [Co(en)3]4[P2Mo5O23]2·9H2O, has been prepared under mild hydrothermal conditions and structurally characterized by elemental analyses, IR spectrum, and single-crystal X-ray diffraction. Yellow crystals crystallized in the triclinic space group with a=10.303(2) Å, b=11.871(2) Å, c=20.288(4) Å, α=99.46(3)°, β=96.39(3)°, γ=115.32(3)°, V=2165.9(8) Å3, Z=1 and R=0.0566. The compound consists of diphosphopentamolybdate clusters, [Co(en)3]3+ complexes, and water molecules, which are held together to generate a three-dimensional supramolecular network via hydrogen-bonding interaction. Interestingly, the three-dimensional supramolecular network contains cyclic water hexamers, which play an important role in the formation of the crystal. [Copyright &y& Elsevier]

Abstract: Two new cobalt (II) containing coordination polymers {Co3[O2C(CH2)4CO2]3[1,10′-phen]2} n (1) and {Co2[O2C(CH2)3CO2]2[1,10′-phen]2} n (2) have been synthesized under the hydrothermal condition and characterized by elemental analyses, IR, TG analyses and the single crystal X-ray diffractions. Crystal data for compound 1: C42H42Co3N4O12, triclinic P-1, a=9.0014(18)Å, b=9.0573(18)Å, c=13.327(3)Å, α=97.93(3), β=100.06(3), γ=104.85(3), Z=1. Crystal data for compound 2: C34H32Co2N4O8, monoclinic P2(1)/c, a=10.537(2)Å, b=20.780(4)Å, c=13.471(3)Å, β=100.63(3), Z=4. Compound 1 exhibits a novel two-dimensional layer framework, in which the trinuclear Co clusters are linked by adipate anions. Compound 2 represents a one-dimensional chain. Furthermore, the magnetic behavior of compound 2 is studied. [Copyright &y& Elsevier]

Abstract: Two novel compounds, (H2bpy)0.5{[Ni(H2O)5][Ni(Hbpy)(H2O)4][Mo5P2O23]} 1 and (H2bpy)0.5{[Co(H2O)5][Co(Hbpy)(H2O)4][Mo5P2O23]} 2, have been prepared under mild hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction. The two compounds are isostructural and crystallize in the triclinic space group with a=10.760(2)Å, b=10.771(2)Å, c=17.566(4)Å, α=98.56(3)°, β=96.66(3)°, γ=111.10(3)°, and Z=2 for the compound 1, and a=10.770(2)Å, b=10.815(2)Å, c =17.684(4)Å, α=98.96(3)°, β=96.41(3)°, γ=111.37(3)°, and Z=2 for the compound 2. Crystal structure analysis reveals that 1 and 2 are not only the first examples of polyoxometalate supported transition metal complexes constructed by diphosphopentamolybdate cluster and transition metal complex fragments but also the first examples of disupporting polyoxometalate compounds where two distinct transition metal complex fragments are supported on the polyoxoanion cluster. [Copyright &y& Elsevier]

Abstract: A unique composite hybrid material [Cu4(bpy)4(H2O)2(PO4)2](H3O)[PMo12O40] 1 (bpy=2, 2′-bipyridine) has been hydrothermally synthesized from the reaction of Na2MoO4·2H2O, H3PO4, Cu(MeCO2)2·H2O, 2, 2′-bpy and water. It has been characterized by elemental analysis, IR, TG, and single-crystal X-ray diffraction. Compound 1 is constructed from the organic–inorganic hybrid [Cu4(bpy)4(H2O)2(PO4)2]2+ cation and α-Keggin [PMo12O40]3- polyoxoanion, which represents the first example of a hybrid material that combines transition metal phosphate and polyoxometalate. [Copyright &y& Elsevier]

An one-dimensional mixed-valence molybdenum oxide [Mo3O8(2,2′-bipy)2] has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Red-brown crystals crystallized in the monoclinic system, space group P2(1)/n, a=9.3674(19), b=16.994(3), c=13.956(3) A˚, β=102.66(3)°, V=2167.7(8) A˚3, Z=4 and R=0.0515. The title compound exhibits an infinite one-dimensional chain with organonitrogen donors of 2,2′-bipy groups coordinated directly to the molybdenum oxide framework, where the binuclear units of edge-sharing {MoO4N2} octahedra are linked by {MoO4} tetrahedra through corner-sharing oxygen atoms. Other characterizations by elemental analysis, IR, and thermal analysis are also described. [Copyright &y& Elsevier]

A new bimetallic cluster complex with the formula [{Co(phen)2}2V4O12]·H2O was synthesized from the hydrothermal reaction of V2O5, H2C2O4, Co(NO3)2, 1,10-phenanthroline (phen), (C4H9)4NOH and water. The compound crystallizes in an orthorhombic system with space group Pbcn and unit cell parameters a=19.106(3) A˚, b=15.250(3) A˚, c=16.321(2) A˚, V=4755.4(13) A˚3, Z=4 and R=0.0318. The bimetallic cluster complex [{Co(phen)2}2V4O12]·H2O is composed of a discrete V4O124− cluster covalently attached to two [Co(phen)2]2+ fragments and the discrete hexanuclear bimetallic clusters of [{Co(phen)2}2V4O12]·H2O are further extended into interesting three-dimensional supermolecular arrays via π–π stacking interactions of phen groups. Other characterizations by elemental analysis, IR, and thermal analysis are also described. [Copyright &y& Elsevier]

Abstract: Two new coordination polymers {[Co2(BTC)(OH)(H2O)2] 2 ·2H2O}n (1) (BTC=1,2,4-benzenetricarboxylate) and {Co2(NA)4(H2O)}n (2) (NA=nicotinate) had been synthesized under the hydrothermal condition and characterized by elemental analyses, IR, and the single crystal X-ray diffraction. Complexes 1 is a new three-dimensional network composed by tetranuclear Co cluster. It can be seen constructed by two-dimensional Co–O inorganic layers supported by BTC ligands. Complex 2 is also a three-dimensional network. To our surprise, Complex 1 and 2 both contain honeycomb-like structure surrounded by Co clusters and BTC, NA ligands. We think it is difficult to construct such structures with asymmetry ligand such as BTC and NA. Furthermore, the thermal stability properties of the two complexes are studied. [Copyright &y& Elsevier]

Abstract: A new compound 1 (phen=phenanthroline) has been synthesized under hydrothermal conditions and characterized by IR, TG analysis and single-crystal X-ray diffraction. The study of the magnetic property of compound 1 exhibits the presence of antiferromagnetic interactions. Compound 1 crystallizes in the monoclinic system, space group P21/c, a =21.843(4)Å, b =16.566(3)Å, c =21.025(4)Å, α =90°, β =100.26(3)°, γ =90°, V =7486(3)Å3, Z =2. The basic building unit in compound 1 is the [PMo12V2O42] cluster. The most remarkable structural feature of 1 is that there exist two distinct [PMo12V2O42] clusters. One is covalently linked by [Co(phen)2] complexes to form 2D covalent layer, the other supports two [Co(phen)2(H2O)] complexes forming a 2D supramolecular network. Such two different kinds of layers are further stacked to form a novel 3D supramolecular framework. [Copyright &y& Elsevier]

Abstract: Two new one-dimensional reduced molybdenum (V) phosphates, [Zn(phen)2][Zn(phen)2(H2O)][Zn(HPO4)8[(MoO2)6(OH)3]2]·H2O (1) and [Co(phen)3][Co(phen)2(H2O)(H2PO4)][KNa(H2O)2][Co(H2O)2][Co(phen)2][Co(H2PO4)2(HPO4)3(PO4)3[(MoO2)6(OH)3]2]·5H2O (2) (phen=1,10-phenanthroline), have been synthesized and characterized by elemental analyses, IR, TG, and single crystal X-ray diffraction. Compound 1 is built up of Zn[P4Mo6]2 cluster as the structural motif covalently linked by [Zn(phen)2] complex subunits to yield unusual one-dimensional chains, which are further in close contact forming two-dimensional supramolecular layers via π–π stacking interactions. In compound 2, Co[P4Mo6]2 clusters are connected by [Co(phen)2], [Co(H2O)2] and [KNa(H2O)2] fragments through covalent bonds, forming an unusual one-dimensional chain. Interestingly, both [Co(phen)3] complex and [Co(phen)2(H2O)(H2PO4)] cobalt phosphate are presented as charge-compensating cations and contact each other via π–π stacking interactions to form a supramolecular chain, then the supramolecular chains link two neighboring chains that contain [P4Mo6] via hydrogen-bonding interactions to form a two-dimensional supramolecular layer. Furthermore, the fluorescent activity of compound 1 is reported. [Copyright &y& Elsevier]

Abstract: An exploration of the cadmium-citrate system under hydrothermal conditions, has led to the isolation of a novel framework [Cd3(H2O)2(C6H5O7)2]n 1. This compound features a novel 2D undulated sheet containing infinite double-stranded helical chains, which is unique among metal-citrate system identified so far. Crystal data for compound 1: Monoclinic, Space group P2 1 /c, a=6.0974(12) Å, b=15.271(3)Å, c=9.781(2)Å, β=102.74(3)°, V=888.3(3)Å3, Z=2. Other characterizations by elemental analysis, IR and TG are also described. [Copyright &y& Elsevier]

Abstract: A novel reduced polyoxometalate derivative [Cu(2,2′-bipy)2][PMoVI 8MoV 4O40{Cu(2,2′-bipy)}2.5]·H2O 1 has been hydrothermally synthesized and characterized by IR and XPS spectra, TG analysis and single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic system, space group P21/c, a=21.620(4)Å, b=19.070(4)Å, c=17.810(4)Å, β=109.99(3)°, V=6901(2)Å3, Z=4. The result of structure determination shows that the reduced α-Keggin polyoxoanion [PMoVI 8MoV 4O40]7− is capped by two divalent Cu atoms through four bridging oxo groups on two opposite {Mo4O4} faces or pits and supports a half {Cu(2,2′-bipy)} complex via the surface bridging oxygen atoms. [Copyright &y& Elsevier]

A new vanadium phosphate [C2N2H10]{(VO)(VO2)[V(OH2)](PO3.5)4}·H2O 1 has been hydrothermal synthesized and structurally characterized by the single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic system, space group P2(1)/c, a=12.3096 A˚, b=11.7570 A˚, c=12.6334 A˚, β=98.103°, V=1810.10A˚3, Z=2, λ(Mo Kα)=0.71073 A˚, R=0.0781 with 4105 reflections. Compound 1 exhibits a three-dimensional (3-D) open-framework structure, which consists of a novel {V3O16} trimer linked by four {PO4} tetrahedra. Furthermore, four such {V3P4O18} structural unit are connected together to form an interesting 10-mumber ring via corner-sharing mode. [Copyright &y& Elsevier]

Two novel dibenzo-18-crown-6 sodium isopolytungstates, [(DB18C6)(CH3OH)Na]2W6O19·DB18C6·H2O 1 and [(DB18C6)(DMF)2Na]4W10O32·2DMF·2H2O 2, have been synthesized in mixed methanol and acetonitrile solvents and characterized by elemental analysis, TGA, IR and single crystal X-ray diffraction. The compound 1 crystallizes in the monoclinic space group C2/c with a=23.182(8), b=19.527(2), c=18.737(3) A˚, β=115.15(2)°, V=7678(3) A˚3, Z=4, and R1(wR2)=0.0611(0.1504). The compound 2 crystallizes in the monoclinic space group P21/n with a=16.516(2), b=22.325(6), c=20.425(7) A˚, β=91.78(2)°, V=7528(3) A˚3, Z=2, and R1(wR2)=0.0397(0.0773). The compound 1 exhibits a novel organic–inorganic sandwich-type structure, in which the crown ether–sodium complexes are coordinated to the terminal oxygen atoms of W6O192−. In compound 2, all Na+ ions are thoroughly enveloped into the organic moieties of crown ether and DMF molecules and are connected with the ‘naked’ polyanions W10O324− via the electrostatic attraction. [Copyright &y& Elsevier]

A novel organic–inorganic hybrid vanadium oxide [V4O10(o-phen)2], involving all vanadium atoms present in +5 oxidation, has been hydrothermally synthesized and characterized by elemental analysis, IR, UV-vis, ESR, XPS spectra and TG-DTA thermal analysis. The single-crystal X-ray diffraction shows that the red-brown crystal is formed in the triclinic system, space group P1¯, a=9.782(2), b=6.5124(14), c=19.765(4) A˚, α=89.94(2)°, β=100.66(2)°, γ=89.86(2)°. The title compound exhibits an infinite one-dimensional ladder-type tetravanadate skeleton with organonitrogen donors of o-phenanthroline ligands coordinated directly to the vanadium oxide framework. [Copyright &y& Elsevier]

As frozen surimi, the key raw material of surimi products, is commonly stored at low temperature, surimi quality especially its protein constantly deteriorates through long periods of storage, thus integrated evaluation of protein denaturation would be essential for quality control of surimi industry. The objective of this study is to investigate the effect of frozen time on surimi by exploring the denaturation mechanism of surimi protein during low temperature storage by Tri-step infrared spectroscopy. During frozen storage, FT-IR peaks of 1219 cm−1, 1238 cm−1 (amide III) and 1396 cm−1 (-CH 3) gradually attenuate from strong to weak and finally disappear, while 1534 cm−1 (amide II), 1611 cm−1 and 1638 cm−1 (amide I) also have obvious changes in surimi. Spectral curve-fitting results disclose that the contents of α-helix and β-sheet are continuously decreased and transformed to random coil and β-turn. 2DCOS-IR results further reveal that the denaturation process of protein can be generally divided into three periods: stable period, slow change period and deterioration period. • The effect of frozen time on surimi mainly reflect on protein denaturation, which could be revealed by Tri-step IR. • Secondary structures can transform into each other during frozen storage. • The denaturation process of protein can be divided into stable, slow change and deterioration period. [ABSTRACT FROM AUTHOR]