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A new oxovanadium(V) complex, [N'-(3-ethoxy-2-hydroxybenzylidene)-4-fluorobenzohydrazido](quinolin-8-olato)oxovanadium(V), [VO(EFH)(QN)], where EFH is the anion ofN'-(3-ethoxy-2-hydroxybenzylidene)-4-fluorobenzohydrazide, and QN is the anion of 8-hydroxyquinoline, was prepared and characterized by elemental analysis, infrared spectra, thermal analysis and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic space groupP21/n, with unit cell dimensionsa= 8.3921(4) Å,b= 28.200(1) Å,c= 10.0237(5) Å, β = 102.394(1)°,V= 2316.9(2) Å3,Z= 4, GOOF = 1.101,R1= 0.0464, andwR2= 0.1081. The V atom is coordinated by the three donor atoms of EFH and two donor atoms of QN, as well as one oxo oxygen group, forming an octahedral coordination. [ABSTRACT FROM AUTHOR]

Two new mononuclear Schiff base nickel(II) complexes, [Ni(ClSal)] (1) and [Ni(MeSal)] (2) (H2ClSal =N,N′-bis(3,5-dichlorosalicylidene)-1,3-pentanediamine; H2MeSal =N,N′-bis(3-methylsalicylidene)-1,2-ethanediamine), have been synthesized and characterized by elemental analyses, infrared spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes in the orthorhombic space groupP212121, with unit cell dimensionsa= 9.788(1) Å,b= 10.206(1) Å,c= 20.458(2) Å,V= 2043.7(4) Å3,Z= 4,R1= 0.0814, andwR2= 0.1689. Complex 2 crystallizes in the monoclinic space groupP21/n, with unit cell dimensionsa= 11.6353(5) Å,b= 11.8807(6) Å,c= 12.8241(6) Å,β= 115.213(1)°,V= 1603.9(1) Å3,Z= 4,R1= 0.0243, andwR2= 0.0675. The Ni atoms in the complexes are four-coordinated in square planar geometry by the N2O2donor set of the ligands. [ABSTRACT FROM AUTHOR]

A new polymeric zinc(II) complex, [ZnL2(PDA)]n, has been prepared by the reaction of zinc sulfate, 4-nitrophenylacetic acid, and propane-1,3-diamine (PDA) in water. Structure of the complex has been characterized by single-crystal X-ray diffraction. The complex crystallizes as orthorhombic space group Pnma, with unit cell dimensions a = 15.732(1) Å, b = 23.912(1) Å, c = 5.5565(3) Å, V = 2090.2(2) Å3, Z = 4, R1 = 0.0427, wR2 = 0.0968, S = 1.048. The Zn atom is coordinated in a tetrahedral geometry. Single crystals of the complex are stabilized by hydrogen bonds and π..π interactions. [ABSTRACT FROM AUTHOR]

Reaction of [MoO2(acac)2] (where acac = acetylacetonate) with two similar hydrazone ligands in ethanol yielded two ethanol-coordinated mononuclear molybdenum(VI) oxo complexes with general formula [MoO2L(EtOH)], where L = L¹ = (N'-(3,5-dibromo-2-hydroxybenzylidene)-4-nitrobenzohydrazide (H2L¹), and L = L² = (N'-(3,5-dibromo-2- hydroxybenzylidene)-2-fluorobenzohydrazide (H2L²). Crystal and molecular structures of the complexes were determined by single crystal X-ray diffraction method. All of the investigated compounds were further characterized by elemental analysis and FT-IR spectra. Single crystal X-ray structural studies indicate that the hydrazone ligands coordinate to the MoO2 cores through enolate oxygen, phenolate oxygen and azomethine nitrogen. The Mo atoms in both complexes are in octahedral coordination. Thermal stability of the complexes has also been studied. [ABSTRACT FROM AUTHOR]

A new mononuclear Schiff base cobalt(III) complex, [Co(MEA) (N3)(DMF)] (1), and a new mononuclear Schiff base manganese(III) complex, [Mn(EEA)(N3)(OH2)] (2) (MEA is bis (5-methoxysalicylidene)ethylenediamine; EEA is bis(6-ethoxys alicylidene)ethylenediamine), have been prepared and structurally characterized by physicochemical and single-cyrstal X-ray diffraction. Complex 1 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 9.910(1) Å,b= 19.279(1) Å,c= 12.410(1) Å,β= 102.729(2)°, V = 2312.8(2) Å3, Z = 4,R1= 0.0319, andwR2= 0.0779. Complex 2 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 14.252(2) Å,b= 22.227(3) Å,c= 13.613(2) Å,β= 91.512(2)°, V = 4310.7(11) Å3, Z = 8,R1= 0.0392, andwR2= 0.0839. The metal atom in each complex is in an octahedral coordination. Crystal of complex 2 was stabilized by hydrogen bonds. [ABSTRACT FROM PUBLISHER]

Five new metal–organic frameworks (MOFs), named [Zn 2 (aobtc)(H 2 O) 4 ] ( 1 ), [Mn 3 (Haobtc) 2 (DMA) 2 (H 2 O) 2 ]·2H 2 O ( 2 ), [Co 3 (Haobtc) 2 (H 2 O) 4 ]·11H 2 O ( 3 ), [Co 3 (aobtc) 2 ]·Himi·H 3 O·3H 2 O ( 4 ), [Cd 2 (aobtc)(bpy)]·4.5H 2 O ( 5 ) (H 4 aobtc = 3,3′,5,5′-azoxybenzenetetracarboxylic acid, bpy = 4,4′-bipyridine, imi = imidazole), have been designed and syntheses. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra and TG analyses. The five compounds exhibit diverse secondary building units (SBUs) and show various structures with different porosity. Compound 1 is a two-dimensional (2D) layer with (4,4)- sql topology based on binuclear Zn cluster (SBU). Both compounds 2 and 3 possess 2D framework with (3,6)-connected kgd topology, based on trinuclear Mn and Co clusters, respectively. Compound 4 shows a 3D framework with (3,8)-connected flu topology, containing linear trinuclear Co clusters as 8-connected nodes. The 3D framework of Compound 5 is built from infinite Cd–O–Cd rod SBUs. The effects of stacking modes on the crystal architectures are discussed. The solid-state photoluminescence for 1 and 5 , the magnetic properties for 2 – 4 , and CO 2 adsorption for 3 were also investigated. [ABSTRACT FROM AUTHOR]

Sumalarins D–G (1 – 4), four previously undescribed curvularin derivatives, along with two known related metabolites, curvularin (5) and dehydrocurvularin (6), were isolated and identified from the mangrove-derived fungus Penicillium sumatrense MA-325. Among them, sumalarin D (1) represents a unique example of curvularin derivative featuring a 5-methylfuran-2-yl-methyl group. Their structures were elucidated based on analysis of NMR and MS data as well as comparison of ECD spectra and quantum chemical calculations of NMR, and compound 1 was confirmed by X-ray crystallographic analysis. Compounds 1 , 2 , 5 , and 6 are active against aquatic pathogenic bacteria Vibrio alginolyticus and V. harveyi with MIC values ranging from 4 to 64 μ g/mL, while compound 6 is cytotoxic against tumor cell lines 5673, HCT 116, 786-O, and Hela with IC 50 values of 3.5, 10.6, 10.9, and 14.9 μ M, respectively. Sumalarin D (1), the first curvularin featuring a unique 5-methylfuran-2-yl-methyl group at C-4, along with three curvularin congeners, were identified from the mangrove-derived Penicillium sumatrense MA-325. [Display omitted] • Four previously undescribed curvularins were isolated from mangrove-derived Penicillium sumatrense. • Sumalarin D (1) is the first curvularin featuring a unique 5-methylfuran-2-yl-methyl group at C-4. • ECD and DP4+ calculation and X-ray diffraction were used for structure determination. • Dehydrocurvularin (6) exhibited potent cytotoxic activities against a panel of tumor cell lines. [ABSTRACT FROM AUTHOR]

Layer-structured oxides Y1-xBixBaCo4O7(0.00 ≤ x ≤ 0.05) were successfully synthesized and their structural and oxygen absorption properties were investigated by x-ray diffraction and thermogravimetry. Though Bi solubility was limited to about 5%, corresponding to Y0.95Bi0.05BaCo4O7, it is found that the structure and oxygen absorption properties of Y1-xBixBaCo4O7 are affected significantly as the Bi content x increases. Rietveld refinement results show that Y1-xBixBaCo4O7(x ≤ 0.05) is single phase with a hexagonal crystal structure (space group P63mc). Unit cell parameters and volume are changed and CoO4 tetrahedra are distorted along the c-axis in Bi doped YBaCo4O7. The TG results show that Y1-xBixBaCo4O7 undergoes two oxygen absorption processes in oxygen from room temperature to 1000°C and the maximum mass increase of the doped samples is less than that of YBaCo4O7. Bi doping effects on the structure and oxygen absorption properties are discussed on the basis of average radius and disorder of the Y site, the valence of Bi and the oxygen activation energy. [ABSTRACT FROM AUTHOR]

Seven novel highly connected metal–organic frameworks (MOFs), formulated as [Co7(aobtc)3(bpy)2(μ3-OH)2(μ2-OH2)2(H2O)4]·4H2O (1), [Ni5(aobtc)2(bpy)2(μ3-OH)2(H2O)6]·4H2O (2), [Zn3(aobtc)2]·H2bpy·H2O (3), [Zn3(aobtc)2]·H2bpp·H2O (4), [Cd3(aobtc)2]·[Me2NH2]2·3H2O (5), [Co3(aobtc)2]·H2bpp·H2O (6) and [Mn3(aobtc)2]·H2bpy·2H2O (7) (H4aobtc = azoxybenzene-3,3′,5,5′-tetracarboxylic acid, bpy = 4,4′-bipyridine, bpp = 1,3-bis(4-pyridyl)propane) have been synthesized and characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction, and thermal analyses. Compound 1 is a 3D (4,4,14)-connected self-penetrating framework with (46)2(45·6)(430·526·631·74) topology based on hexanuclear clusters as 14-connected nodes. To our knowledge, compound 1 represents the highest connected self-penetrating topology presently known in the entangled system. Compound 2 displays a trinodal (4,4,10)-connected network with (46)(45·5)(410·518·612·75) topology based on tetranuclear clusters as 10-connected nodes. Compounds 3–7 exhibit (4,8)-connected flu nets based on trinuclear clusters as 8-connected nodes, and these five MOFs show similar structures but different pore volumes mainly associated with the change of the species of guest molecules. Structural analyses of 1–7 demonstrate that increasing the metal nuclearity is a practical method to obtain highly connected coordination networks based on metal clusters as nodes. In addition, the magnetic properties of 1, 2, 6, and 7 and the luminescence properties of compounds 3–5 have also been studied. [ABSTRACT FROM AUTHOR]

Six new coordination polymers, namely [Co 2 (1,2-bdc) 2 (bibp) 2 ]·H 2 O ( 1 ), [Zn 2 (1,2-bdc) 2 (bibp) 2 ]·H 2 O ( 2 ), [Ni 2 (1,2-bdc) 2 (bibp) 3 ]·7H 2 O ( 3 ), [Cd(1,2-bdc)(bibp) 0.5 ] ( 4 ), [Co(Hbtc)(bibp)] ( 5 ), [Cd(Hbtc)(bibp)] ( 6 ) (bibp = 1,4-bis(4-(imidazole-1-yl)benzyl)piperazine, 1,2-bdc = 1,2-benzenedicarboxylate, btc = 1,3,5-benzenetricarboxylate), have been synthesized under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra and TG analyses. Compounds 1 – 6 display different 2D → 3D interdigitated structures due to their different 2D layers. In 1 and 2 , the 2D layers contain single-stranded meso- helical chains. In 3 , there are large rhombic cavities in the 2D sheet. In 4 , the 2D layer is built from rod-shaped SBUs. In 5 and 6 , the 2D layers exhibit highly undulating 4 4 - sql networks. In addition, the magnetic properties for compounds 1 , 3 and 5 , and the photoluminescence properties for compounds 2 , 4 and 6 have also been investigated. [ABSTRACT FROM AUTHOR]

Two novel polyoxometalate (POM)-based organic–inorganic hybrids, namely, [(CH 3 ) 2 NH 2 ][Co(tpba)(Mo 2 O 7 )]·2H 2 O ( 1 ) and [(CH 3 ) 2 NH 2 ][Ni(tpba)(Mo 2 O 7 )]·2H 2 O ( 2 ) (tpba = 4-([4,2′:6′,4′′-terpyridin]-4′-yl)benzoic acid), have been synthesized and characterized by elemental analyses, IR spectra, TG analyses and single-crystal X-ray diffraction. Compounds 1 and 2 are isostructural and feature microporous interpenetrated frameworks, which are constructed from metal–organic layers pillared by the [Mo 2 O 7 ] 2 − anions. Topologically, the overall structures of 1 and 2 can be classified as a rare (3,5)-connected twofold interpenetrated hms net, which has never been observed in POM-based hybrid materials prior to this work. Furthermore, the magnetic property of compound 1 are discussed. [ABSTRACT FROM AUTHOR]

Three novel pillared-layer molybdenum-oxide-based inorganic–organic hybrids, namely, [Zn 2 (tyty)(μ 3 -OH)(MoO 4 )(H 2 O)] ( 1 ), [Co 2 (tyty)(μ 3 -OH)(MoO 4 )(H 2 O)] ( 2 ) and [Co(pytpy) 2 (Mo 4 O 13 )] ( 3 ) (Htyty = 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene, pytpy = 4′-(4-pyridyl)-4,2′:6′,4″-terpyridine), have been synthesized and characterized by elemental analyses, IR spectra, TG analyses and single-crystal X-ray diffraction. Compounds 1 and 2 are isostructural and display 3D pillared-layer frameworks based on bimetal-oxide layers pillared by the tyty ligands. Compound 3 shows a 3D pillared-layer framework constructed by pytpy coordinating directly to a molybdenum atom and Co atom simultaneously. Furthermore, the photoluminescence property of compound 1 and the magnetic properties of compounds 2 and 3 are discussed. [ABSTRACT FROM AUTHOR]

Two new isostructural metal-organic frameworks, namely [Co(HL)(bpp)] · 0.5H 2 O (1) and [Zn(HL)(bpp)] · 3H 2 O (2) (H 3 L = 5-(2′-carboxy-biphenyl-4-ylmethoxy)-isophthalic acid, bpp = 1,3-bis(4-pyridyl)propane), have been hydrothermally synthesized and further characterized by single crystal X-ray diffraction, powder X-ray diffraction, elemental analyses, IR spectra and TG analyses. Compounds 1 and 2 exhibit interesting 3D frameworks of (6 5 .8)-CdSO 4 topology with dangling arm (i.e. the uncoordinated 2′-carboxy-biphenyl-4-ylmethoxy group of HL ligand). The remarkable feature of these two compounds is that each dangling arm threads into two 6-membered rings belonging to the 3D net itself, displaying the self-threading character. The magnetic properties of 1 and photoluminescence of 2 have also been investigated. [ABSTRACT FROM AUTHOR]

We characterize the structures of Ge1–xSnx films with x up to 0.14 grown on Ge (00l) by molecular-beam epitaxy at low temperature. The results show that Ge1–xSnx films are fully strained even at high Sn composition. The in-plane lattice parameters remain exactly the same as that of the substrate. Depth sensitivity analysis of the lattice parameters indicates that the strains of the epitaxial films are all in homogeneity. The films are fully strained. Poisson ratios, the force constants for the bonds between Ge and Sn are estimated and discussed in the present paper. Raman results show Ge—Ge, Ge—Sn, Sn—Sn vibrational modes. The Sn—Sn bond aggregation may respond to the high quality of our films. The fully strained epitaxy films with high content of Sn may be useful in designing the high quality GeSn films. [ABSTRACT FROM AUTHOR]