Crystal Structure and Spectroscopic Properties of a New Ternary Tungstate Li3Ba2Ho3（WO4）8

A single crystal of Li3Ba2Ho3(WO4)8 was obtained from a flux of Li2WO4 under an air atmosphere. The structure of the pure crystal was determined by single-crystal X-ray diffraction method. It crystallizes in the monoclinic system, space group C2/c with a = 5.240(4), b = 12.790(10), c = 19.247(15), β = 91.921(15)°, V = 1289.1(18)3, Z = 2, Mr = 2773.09, Dc = 7.144 g/cm3, μ = 47.732 mm-1, Rint = 0.0693, F(000) = 2340, the final R = 0.0472 and wR = 0.1221 for 1535 observed reflections (I > 2σ(I)). The Li3Ba2Ho3(WO4)8 has a high structure disorder with one 8f site shared by Li(1) and Ho ions with occupancy of 0.25 and 0.75, respectively. The fundamental structure is constituted by distorted square antiprisms Ho/Li(1)O8 with C1 symmetry, distorted Li(2)O6 octahedra and BaO10 polyhedra. The optical properties were investigated by IR and absorption spectroscopy, and the emission cross sections and gain cross sections of 5I7 → 5I8 of Ho3+ were calculated.     

Synthesis, Crystal Structure and Photoluminescence of a 2D Two-fold Interpenetrating Cd(Ⅱ) Coordination Polymer Based on a Flexible Reduced Schiff Base Ligand

<正>By the reaction of cadmium chloride with a reduced Schiff base ligand (H_2L = N-(4- carboxybenzyl)-glycine), a novel Cd(II) compound [Cd(HL)_2]·4H_2O (1) has been obtained. Single-crystal X-ray diffraction analysis reveals that it crystallizes in orthorhombic, space group Pbcn with a = 13.9788(8), b = 24.4204(14), c = 13.9580(8), V = 4764.8(5)~3, Z = 8, M_r = 600.84, D_c = 1.675 g/cm~3, μ = 0.983 mm~(-1), F(000) = 2448, S = 1.084, R = 0.0806 and wR = 0.1705 (I > 2σ(I)). It displays a 2D two-fold interpenetrating structure. The Cd(II) ions are six-coordinated. The cross-linkage of Cd(II) ions by the bridge of HL anions results in a [Cd(HL)_2] layer. Every two [Cd(HL)_2]_n layers are penetrated with each other, resulting in a two-fold interpenetrating double-layer structure by π-π stacking interactions and hydrogen bonds. Such double-layers are further linked by hydrogen bonds into a supramolecular structure. Photoluminescent investigation shows that compound 1 displays strong emission in the purple region.     

A Novel Three-dimensional Ni Coordination Polymer Based on Flexible Di-carboxylate Ligand and 4,4-Pyridine： Synthesis, Characterization and Topological Analysis

A novel Ni(II) coordination polymer [Ni(dtba)(4,4′-bpy)] (1, H2dtba = 2,2′-dithio- bisbenzoic acid, 4,4′-bpy = 4,4′-bipyridine) has been synthesized by H2dtba and Ni(CH3COO)2·4H2O with exo-bidentate rigid ligand 4,4′-bpy by using hydrothermal method, and its structure was determined by single-crystal X-ray diffraction. X-ray crystal structure analysis reveals that complex 1 crystallizes in monoclinic, space group Cc with a = 11.7624(9), b = 18.7933(19), c = 10.3071(11), β = 97.6510(10)°, V = 2258.2(4)3, Z = 4, C24H16N2NiO4S2, Mr = 519.22, Dc = 1.527 g/cm3, μ = 1.079 mm-1 and F(000) = 1064. The structure was solved by direct methods and refined to R = 0.0434 and wR = 0.1000 for 3281 observed reflections (I > 2σ(I)). The coordination environment of Ni(II) is a distorted octahedron, and a three-dimensional structure was formed with the coordination effect of dtba2- and 4,4′-bpy ligands. The topological analysis reveals that the whole framework of 1 is a 2-nodal net of (52.6)(53.64.72.8) topology. The thermal stability and XRD pattern of 1 were also investigated.     

Hydrothermal Synthesis of a 1D Paddle-wheel Cu(Ⅱ) Coordination Polymer {[Cu_2(NBDOA)_2·(H_2O)_2]·2(H_2O)}_n Constructed by Flexible Carboxylic Acid

A 1-D paddle-wheel copper (II) coordination polymer constructed by 2-nitro-benzene-1,4-di(oxyacetic) acid has been synthesized by hydrothermal reaction,and its crystal structure was determined by X-ray diffraction. The crystal is of triclinic,space group P1 with a=7.7257(12),b=8.3648(13),c=11.5516(18),α=76.654(2),β=82.088(2),γ=63.636(2)o,C20H22Cu2N2O20,Mr=737.48,V=650.27(18)3,Dc=1.883 g/cm3,F(000)=374,μ=1.737 cm-1 and Z=1. The final refinement gave R=0.0345 and wR=0.0995 for 1996 observed reflections with I > 2σ(I). The coordination polymer demonstrates a 1-D microporous structure,and the channel is formed by two NBDOA2-and two Cu2+ ions. The ligand NBDOAH2 displays a good flexible characteristic. The 1-D chains are connected to a 3-D supramolecular network by hydrogen bonds.     

Synthesis,Crystal Structure and Bioactivity of N-（phenethylcarbamothioyl）cyclopent-1-enecarboxamide

The compound N-(phenethylcarbamothioyl)cyclopent-1-enecarboxamide was synthesized by the reaction of cyclopent-1-enecarbonyl isothiocyanate with phenethylamine in acetone, and its structure was characterized by IR, 1H NMR and X-ray crystal structure determination. The crystal of the title compound belongs to triclinic, space group P1 with a = 6.9500(7), b = 9.4618(9), c = 11.3256(11), α = 71.522(9), β = 81.830(8), γ = 89.237(8)o, Z = 2, V = 698.80(12)3, Dc = 1.304 g/cm3, μ = 0.225 mm-1, F(000) = 292, R = 0.0413 and wR = 0.1073 for 1996 observed reflections with I 2σ(I). Intramolecular N(2)–H(2)···O(1) interactions as well as intermolecular N(2)–H(2)···O(1), N(1)–H(1)···S(1) and C(12)–H(12)···S(1) hydrogen bonds help to stabilize the crystal structure. X-ray diffraction analysis reveals that the structure of the new compound exhibits a one-dimensional infinite chain-like structure. The cytotoxicity of the compound was investigated by MTT assay. The results show that the compound is toxic to A549 tumor cell.     

Crystal Structure, Photoluminescent, and Theoretical Studies of 3-Acetyl-8-methoxy-coumarin

The structure of 3-acetyl-8-methoxy-coumarin (AMC) was verified by single-crystal X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a=15.073(3), b=13.068(3), c=11.549(2), β=119.92(3)o, V=1971.7(7)3 , Z=8, F(000)=912, D c=1.470 Mg/m3 , Mr=218.20, μ=0.111 mm-1 , the final R=0.0340 and wR=0.0968 for 1446 observed reflections with I > 2σ(I). The UV-vis absorption and fluorescence of AMC were discussed. The compound exhibits strong blue emission under ultraviolet light excitation. The molecular structure of AMC was optimized using density functional theory (DFT) at the B3LYP/6-31G(d) level, showing that the optimized geometer parameters are in good agreement with the experiment data. In addition, the HOMO and LUMO levels of AMC were deduced.     

Crystal Structure and Conformation of an Imino Sugar

The title compound 3 was synthesized and characterized by IR,NMR and H-RMS,and its crystal structure was determined by X-ray diffraction analysis. The crystal is of monoclinic system (C16H23NO7S,Mr=373.41),space group P21,with a=12.000(2),b=5.5970(11),c=13.689(3),β=93.25(3)°,V=917.9(3)3,Z=2,Dc=1.351 g/cm3,F(000)=396,μ=0.213 mm-1,the final R=0.0489 and wR=0.0777 for observed reflections (I > 2σ(I)). Three intramolecular and three intermolecular hydrogen bonds were found. The absolute configuration of this molecule was confirmed by comparing with the original material.     

Determination of trace Pb(Ⅱ), Cd(Ⅱ) and Zn(Ⅱ) using differential pulse stripping voltammetry without Hg modification

In this work,we reported a simultaneous determination approach for Pb(II),Cd(II)and Zn(II)atμg L 1concentration levels using differential pulse stripping voltammetry on a bismuth film electrode(BiFE).The BiFE could be prepared in situ when the sample solution contained a suitable amount of Bi(NO)3,and its analytical performance was evaluated for the simultaneous determination of Pb(II),Cd(II)and Zn(II)in solutions.The determination limits were found to be 0.19μg L 1for Zn(II),and0.28μg L 1for Pb(II)and Cd(II),with a preconcentration time of 300 s.The BiFE approach was successfully applied to determine Pb(II),Cd(II)and Zn(II)in tea leaf and infusion samples,and the results were in agreement with those obtained using an atomic absorption spectrometry approach.Without Hg usage,the in situ preparation for BiFE supplied a green and acceptability sensitive method for the determination of the heavy metal ions.     

A Unique 2D Layered Fe~(Ⅲ) Coordination Polymer with only Formate Ligand as Bridges: Synthesis,Crystal Structure and Magnetic Properties

A novel two-dimensional layered Fe~(Ⅲ) formate, Fe(HCO_2)_2ClH_2O, has been synthesized by solvothermal reaction. The structure of complex is characterized by single-crystal X-ray diffraction. The complex crystallizes in tetragonal space group P4/nmm with a = 5.9588(6), c = 8.3831(17) ?, V = 297.66(7) ?~3, Z = 2, F(000) = 198, Dc = 2.224 g/cm~3, Mr = 199.35, μ = 2.927 mm~(-1), the final R = 0.0231 and w R = 0.0585(I 2σ(I)) for all data. Single-crystal structure analysis indicates that the complex has a 2D metal formate structure with only formate anions as bridges. The anti-anti formats link the FeⅢ ions to form a(4, 4) net, while the chlorine ions and water molecules coordinate to Fe~(Ⅲ) on both sides of the layer. Magnetic study have shown that an antiferromagnetic interactions between the FeⅢ ions in the complex. And a field induced spin-flop was detected at low temperature.     

Synthesis and Crystal Structure of a New Complex [Cd（C20H14N4）2Cl2]

The title compound [Cd(C20H14N4)2Cl2] 1 was synthesized via the hydrothermal reaction of CdCl2·7H2O and NaOH with 1,3-bis(benzimidazol-2-yl)benzene (BMB), and characterized by elemental analysis and infrared spectra. The crystal of 1 crystallizes in monoclinic, space group C2/c with a = 21.021(6), b = 9.489(3), c = 18.302(6), β = 108.686(6)o, V = 3458.2(19)3, Z = 4, C40H28CdN8Cl2, Mr = 804.01, Dc = 1.544 g/cm3, F(000) = 1624 and μ(MoKα) = 0.829 mm-1. The final R = 0.0306 and wR = 0.0779 for 3334 observed reflections with I > 2σ(I) and R = 0.0796 and wR = 0.0360 for all data. The cadmium atom is four-coordinated by the BMB ligands and Cl atom with a tetrahedral geometry. The extensive N-H···N hydrogen bonding interactions are observed in the structure, which further extend the [Cd(C20H14N4)2Cl2] units into a 1D structure. The thermogravimetric analysis measurement showed that compound 1 has thermal stability as no strictly clean weight loss step occurred below 425 ℃.     

Crystal structure and quantum chemical investigation of [Cd(NTO)_4Cd(H_2O)_6]·4H_2O

The common explosives, RDX (1,3,5-trinitro-1,3,5-triazacyclohexane), HMX (1,3,5,7- tetranitro-1,3,5,7-tetraazacyclooctane) and TNT (trinitrotoluene), were considered adequately for all weapons applications. Due to many catastrophic explosions resulting from unintentional initia-tion of impact, friction or shock, these explosives have become less attractive. TATB (1,3,5-tria- mino-2,4,6-trinitrobenzene) is noted for its insensitivity, however, it does not have the energetic performance of e…     

Synthesis and Crystal Structure of a Zeolite-like Metal-organic Framework Based on the Triazole Ligand

A novel zeolite-like metal-organic framework, [Cd12（trz）12＇F10＇（SiF6）3]·（H3O）4 （Htrz = 1,2,4-triazole）, has been synthesized under solvothermal conditions using 1H-l,2,4-triazole-3- carboxylic acid and CdF2 as the starting materials. The complex has been characterized by elemental analysis, IR, SEM-EDS, gas adsorption, powder and single-crystal X-ray diffraction analyses. The title complex crystallizes in the cubic 1-43m space group, with a = 14.6436（8）, V= 3140.1（3）A3, Z = 2, Mr = 2857.96, D,.= 3.023 g/cm3 and F（000） = 2668. The final R = 0.0653 and wR = 0.1880 for 586 observed reflections with 1 〉 2σ（I）. In the title complex, three adjacent Cd（ll） centers are connected by three p3-bridging triazole ligands to form triagonal secondary building units （SBUs）, which are further interconnected to form a three-dimensional skeleton with tetrahedral cages.     

Solvothermal Synthesis of a 3D Luminescent Cadmium-organic Framework with msw Topological Net

A new cadmium-organic framework, [Cd2（TBDC）2（DMF）2（H2O）]n （1）, was synthesized by solvothermal reaction of rigid carboxylate ligand 2,3,5,6-tetramethyl-l,4-ben- zenedicarboxylate （H2TBDC） and cadmium nitrate and characterized by elemental analysis, infrared spectrum, thermal analysis, PXRD, single-crystal X-ray diffraction and photoluminescence in the solid state. Compound 1 crystallizes in orthorhombic, space group Pca21 with a = 21.487（6）, b = 7.790（2）, c = 20.666（6） A, C30H40Cd2N2O11, Mr = 829.44, V= 3459.3（16） A3, Z = 4, Dc = 1.593 g.cm-3,μ = 1.29 mm-1, F（000） = 1672, 2.7〈θ〈27.2°, λ（MoKa） = 0.71073 A, T= 293（2） K, the final R = 0.026, wR = 0.0548 and S = 1.027. X-ray diffraction analysis reveals that complex 1 possesses a 3D framework and exhibits rnsw net. Thus, the solid-state luminescent spectrum of 1 displays that the emission of cadmium（lI） complex shows a peak at 317 nm upon 250 nm excitation at room temperature.     

Preparation, crystal structure, and thermal stability of the cadmium sulfide nanoclusters Cd6S44+ and Cd2Na2S4+in the sodalite cavities of zeolite A (LTA)

The crystal structure and thermal stability of two cadmium sulfide nanoclusters prepared in zeolite A (LTA) have been studied by XPS, TGA, and single-crystal and powder XRD. The crystal structures of Cd2.4Na3.2(Cd6S4)0.4(Cd2Na2S)0.6(H2O)> or =5.8[Si12Al12O48]-LTA (a = 12.2919(7) A, crystal 1 (hydrated)) and /Cd4Na2(Cd2O)(Na2O)/[Si12Al12O48]-LTA (a = 12.2617(4) A, crystal 2 (dehydrated)) were determined by single-crystal methods in the cubic space group Pm3m at 294(1) K. Crystal 1 was prepared by ion exchange of Na12-LTA in an aqueous stream 0.05 M in Cd2+, followed by washing in a stream of water, followed by reaction in an aqueous stream 0.05 M in Na2S. Crystal 2 was made by dehydrating crystal 1 at 623 K and 1 x 10(-6) Torr for 3 days. In crystal 1, Cd6S4(4+) nanoclusters were found in and extending out of about 40% of the sodalite cavities. Central to each Cd6S4(4+) cluster is a Cd4S4 unit (interpenetrating Cd2+ and S2- tetrahedra with near Td symmetry, Cd-S = 2.997(24) A, Cd-S-Cd = 113.8(12) degrees, and S-Cd-S = 58.1(24) degrees). Each of the two remaining Cd2+ ions bonds radially through a 6-ring of the zeolite framework to a sulfide ion of this Cd4S4 unit (Cd-S = 2.90(8) A). In each of the remaining 60% of the sodalite cavities of crystal 1, a planar Cd2Na2S4+ cluster was found (Cd-S/Na-S = 2.35(5)/2.56(14) A and Cd-S-Cd/Na-S-Na = 122(5)/92(7) degrees). Cd6S4(4+) and Cd2Na2S4+ are stable within the zeolite up to about 700 K in air. Upon vacuum dehydration at 623 K, all sulfur was lost (crystal 2). Instead as anions, only two oxide ions remain per sodalite unit. One bridges between two Cd2+ ions (Cd2O2+, Cd-O = 2.28(3) A) and the other between two Na+ ions (Na2O, Na-O = 2.21(10) A).     

Syntheses,Crystal Structures and Thermal Properties of Two Dicadmiun（Ⅱ） Complexes CdeLeX2 （HL = N-（3-Methoxylsalicylidene）-3- dimethylaminopropylamine,X = Cl （1）, NCS （2））

Two Cd（Ⅱ） complexes, Cd2L2Cl2 （1） and Cd2L2（NCS）2 （2） （HL = N-（3-methoxylsalicylidene）-3-dimethylaminopropylamine） were synthesized and determined by EA, IR, TG and single-crystal X-ray diffraction. The crystallographic data are as follows： monoclinic, space group P21/n, a = 9.2710（9）, b = 18.0069（18）, c = 18.5562（19） A^°, β= 99.741（4）°, V = 3053.1（5）, Z = 4,μ = 1.605, F（000） = 1536, R = 0.0264 and wR = 0.0699 for 1; orthorhombic, space group Pca21, a = 16.196（3）, b = 11.506（2）, c = 36.126（7） A^°, V = 6732（2）, Z = 8,μ = 1.428, F（000） = 3264, R = 0.0376 and wR = 0.0877 for 2. There are two geometrically different octahedral Cd（Ⅱ） atoms, with N4O2 and O4Cl2 donor sets for 1 while N4O2 and N2O4 for 2. In the dinuclear Cd（Ⅱ） centers, the Cd（Ⅱ） atoms are held together by two deprotonted phenolate oxygen atoms from tetradentate L^- ligands. The thermal gravity data show two step decompositions with the residues of CdO for two complexes.     

Isolation and Identification of 5,3′,4′-Trihydroxy-7-methoxyflavanone from Artemisia sphaerocephala Kraschen

5,3′,4′-Trihydroxy-7-methoxyflavanone was isolated from Artemisia sphaeroce- phala Kraschen and characterized by 1H-NMR, 13C-NMR, EI-MS, IR, UV spectra, and single- crystal X-ray diffraction. The title compound crystallizes in orhtorhombic space group Pca21, with a = 14.393(3), b = 5.1629(12), c = 36.919(9), V = 2743.4(11)3, Z = 8, Mr = 302.27, Dc = 1.464 g/cm3, F(000) = 1264, μ = 0.113 mm-1, S = 1.015,(Δ/σ)max = 0.000, the final R = 0.0757 and wR = 0.1809. Structural analysis indicates the title compound consists of two 5,3′,4′-trihydroxy- 7-methoxyflavanone enantiomers in a well-defined arrangement within the crystal lattice, which constructs a three-dimensional network by means of multiple O–H···O hydrogen bonds.     

Synthesis and Crystal Structure of Ethyl 2-（6-（1,3-Dioxo-4,5,6,7-tetrahydro-lH- isoindol-2（3H）-yl）-7-fluoro-3-oxo-2H- benzo[b][1,4]oxazin-4（3H）-yl） Butanoate

The title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469（2）, b = 16.7715（5）, c = 13.7153（4） A, β= 104.9680（10）°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08（10） ,A3, Z= 4, Dc = 1.376 g/cm3, F（000） = 904, T= 296（2） K, R = 0.0508 and wR = 0.1478.     

Ce和Dy在Cd0.5Zn0.5B4O7中的发光特性及能量双向传递

采用高温固相法制备了白蓝光双发射为一体的Cd0.5Zn0.5B4O7∶Ce/Dy系列发光材料. 由XRD测得Cd0.41Zn0.5B4O7∶Ce0.04/Dy0.02的晶胞参数: a=1.3885 nm, b=0.8020 nm, c=0.8670 nm, 属于正交晶系, Pbca空间群. 在Ce/Dy双掺的体系中存在Ce3+和Dy3+两种发光中心, 254~350 nm激发主要是Dy3+的 4F9/2→6H15/2和4F9/2→6H13/2跃迁发射, 而355—390 nm激发主要为Ce3+的5d→4f跃迁发射. 340 nm激发Ce/Dy双掺发光体的发射强度是同浓度Dy3+单掺的31倍, Ce3+是Dy3+的高效敏化剂, 而355—390 nm激发Dy3+是Ce3+的敏化剂. 体系中存在少见的Ce3+→Dy3+与Dy3+→Ce3+的能量双向传递.     

Two Novel Zn（ll）-biphenyl-3,4,5-tricarboxylate Coordination Polymers： Syntheses,Crystal Structures and Luminescence Properties

Two novel Zn（II）-organic frameworks [（CH3）2NH2][Zn（BPT）]＇0.5DMF （1） and [Zn2（HBPT）2（1,4-bis）] （2） （H3BPT = biphenyl-3,4,5-tricarboxylic acid, 1,4-his = 1,4-bis（1H- imidazol-1-yl）butane） have been synthesized under solvothermal conditions, and characterized by IR spectroscopy, powder X-ray diffractions （PXRD） and single-crystal X-ray diffractions. Complex l displays a rtl rutile 3,6-connected network with {4.62}2{42.610.83} topology, while with the 1,4-his secondary ligand being introduced into the assembly, a different structure 2 has been obtained. Compound 2 forms a 2D layered framework through linking by both BPT and 1,4-bis ligands, which is further stacked via hydrogen-bonding interactions to a three-dimensional supramolecular architecture. Furthermore, thermal analyses （TGA） and photoluminescent properties of I and 2 are also investigated in detail.     

Synthesis, Structure and Luminescence of a Novel 2D Cadmium Coordination Polymer with a Ligand Generated in situ

The hydrothermal reaction of 1,2-dicyanobenzene with NaN3 in the presence of Cd(NO3)2 affords a novel 2D cadmium tetrazolyl-benzoate,{Cd(tzbz)(H2O)}n (H2tzbz is 2-(5-tetrazolyl)-benzoate). The tzbz ligand is generated in situ through the 2+3 Sharpless cycloaddition reaction and hydrolyzation. Its crystal structure was determined by single-crystal X-ray diffraction method. The crystal crystallizes in the orthorhombic system,space group Pbca with a=9.6659(19),b=7.6366(15),c=25.964(5) ,V=1916.5(7) 3,Z=8,Mr=318.57,Dc= 2.208 g/cm3,F(000)=1232 and μ=2.276 mm-1. The Cd(Ⅱ) atom is coordinated by four tzbz ligands and one water molecule to form a severely distorted pentangle bipyramid. While each tzbz ligand connects to four Cd(Ⅱ) atoms in a μ4-η1,η2,η1,η1,η1 coordination mode to construct a 2D architecture of the title complex. Additionally,the title complex exhibits strong fluorescence at room temperature in the solid state.