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1.
4′‐Methylazobenzene‐2‐sulfenyl thio‐cyanate (MABS‐SCN) was synthesized in an aqueous medium and characterized by 1H nuclear magnetic resonance, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, and elemental analysis. The crystal structure was confirmed by single crystal X‐ray diffraction and its geometry was optimized in ground state by Hartree–Fock model and (B3LYP) density functional theory, and in solution (ethanol) using polarized continuum model at restricted HF using the basis set 6–31+G*. The compound crystallizes in orthorhombic space group Pbca, with unit cell parameters a = 7.165 (7) Å, b = 18.846 (2) Å, c = 20.379 (2) Å, V = 2752.1 (5) Å3, and Z = 8. It attains a planar thiadiazolium salt structure due to strong ortho azo–sulfur interaction imparting exceptional thermal stability, nonreactive solubility in aqueous medium, and high melting crystalline solid nature. A weak intramolecular C H…S type interaction, one C H…S type, four C H…N type intermolecular hydrogen bonds, and van der Waal's interactions are believed to be the stabilizing force for the crystal structure. MABS‐SCN was also tested for antimicrobial activity.  相似文献   

2.
In the course of investigations relating to magnesia oxysulfate cement the basic magnesium salt hydrate 3Mg(OH)2 · MgSO4 · 8H2O (3–1–8 phase) was found as a metastable phase in the system Mg(OH)2‐MgSO4‐H2O at room temperature (the 5–1–2 phase is the stable phase) and was characterized by thermal analysis, Raman spectroscopy, and X‐ray powder diffraction. The complex crystal structure of the 3–1–8 phase was determined from high resolution laboratory X‐ray powder diffraction data [space group C2/c, Z = 4, a = 7.8956(1) Å, b = 9.8302(2) Å, c = 20.1769(2) Å, β = 96.2147(16)°, and V = 1556.84(4) Å3]. In the crystal structure of the 3–1–8 phase, parallel double chains of edge‐linked distorted Mg(OH2)2(OH)4 octahedra run along [–110] and [110] direction forming a pattern of crossed rods. Isolated SO4 tetrahedra and interstitial water molecules separate the stacks of parallel double chains.  相似文献   

3.
Two coordination polymers, namely [Zn(L)Cl] ( 1 ) and [Zn(L)2] ( 2 ) [L = 4‐(pyridin‐4‐ylmethoxy)benzolic acid] were synthesized under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction analyses, powder X‐ray diffraction, and thermogravimetric analysis. Compounds 1 and 2 have a two‐dimensional square‐shaped structure (the dimensions are 15.43 × 15.43 Å for 1 and 12.064 × 15.017 Å for 2 ) with (44 · 62) topology. Moreover, compounds 1 and 2 exhibit a 3D supramolecular structure made up by strong π–π interactions from the adjacent layers. Furthermore, compounds 1 and 2 show good fluorescence properties in the solid state at room temperature.  相似文献   

4.
The crystalline structure of mangiferin (=2‐β‐D ‐glucopyranosyl‐1,3,6,7‐tetrahydroxy‐9H‐xanthen‐9‐one; 1 ), a biologically active xanthenone C‐glycoside, isolated from the stem bark of Mangifera indica (Anacardiaceae), was unambiguously determined by single‐crystal X‐ray diffraction (XRD). The crystal structure is summarized as follows: triclinic, P1, a=7.6575(5), b=11.2094(8), c=11.8749(8) Å, α=79.967(5), β=87.988(4), γ=72.164(4)°, V=955.3(1) Å3, and Z=2. The structure also shows two molecules in the asymmetric unit cell and five crystallization H2O molecules. The packing is stabilized by several intermolecular H‐bonds involving either the two symmetry‐independent mangiferin molecules 1a and 1b , or the H2O ones.  相似文献   

5.
A novel metal–organic compound [Fe (ox)(phen)]n (phen = 1,10‐Phennannthroline, ox = oxalate acid) has been hydrothermally synthesized and structurally characterized by X‐ray single‐crystal diffraction, X‐ray diffraction, IR, UV–vis diffuse reflectance spectroscopy and X‐ray photoelectron spectroscopy. The compound crystallized in monoclinic,space group P21 with a = 0.92289 (3) nm, b = 1.35719 (3) nm, c = 1.02012 (4) nm,β = 94.372 (2)°,V = 1.27402(8)nm3,Z = 2,and exhibited a 2D layer structure. The photocatalytic activities of the compound were evaluated by decomposing Rhodamine B (RhB) and methyl orange (MO) under the visible light irradiation. In addition, the mechanism of the photocatalytic properties were proposed during this process.  相似文献   

6.
The EuAuGe‐type CaAuSn phase has been synthesized and single‐crystal X‐ray diffraction analysis reveals that it has an orthorhombic symmetry (space group Imm2), with a = 4.5261 (7) Å, b = 7.1356 (11) Å and c = 7.8147 (11) Å. The structure features puckered layers that are connected by homoatomic Au—Au and Sn—Sn interlayer bonds. This structure is one of the two parent structures of its high‐temperature polymorph (ca 873 K), which is an intergrowth structure of the EuAuGe‐ and SrMgSi‐type structures in a 2:3 ratio.  相似文献   

7.
Two new inorganic–organic vanadate hybrid compounds [Mn(Hbbi)2(V4O12)] ( 1 ) and [Cd(Hbbi)2(V4O12)] ( 2 ) (bbi = 1,1’‐(1,4‐butanediyl)bis(imidazole)) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, TG and single‐crystal X‐ray diffraction. The two compounds crystallize in monoclinic system, P21/c space group with a = 8.556(5) Å, b = 10.761(5) Å, c = 16.917(5) Å, β = 93.032(5) o, V = 1555.4(12) Å3, Z = 2, R = 0.0390 for 1 and a = 8.657(5) Å, b = 10.743 (5) Å, c = 16.864 (5) Å, β = 93.81(5)o, V = 1564.9 (12) Å3, Z = 2, R = 0.0717 for 2 . Single‐crystal X‐ray diffraction analysis reveals that the two compounds are isostructural and both consist of one‐dimensional (1D) chains, which are constructed from vanadate anion clusters and [M(Hbbi)2]4+ cation groups [M = MnII ( 1 ), CdII ( 2 )]. Moreover, the polymeric chains are ultimately packed into a three‐dimensional (3D) supramolecular framework through C–H ··· O and N–H ··· O hydrogen bonding interactions.  相似文献   

8.
The crystal structure of the ordered double perovskite Sr2MnTeO6 has been refined at ambient temperature from high resolution neutron and X‐ray powder diffraction data in the monoclinic space group I 1 2/m 1 with a = 5.6166(1) Å, b = 5.5807(1) Å, c = 7.8797(1) Å and β = 90.048(2)°. The structure is the result of out‐of‐phase (–) rotations of virtually undistorted NiO6 and TeO6 octahedra in the (0 – –) sense about two of the axes of the ideal cubic perovskite. Electron diffraction measurements have been used to confirm the proposed space group and structure.  相似文献   

9.
At 1050 ?C boron combines with sodium forming a boride of formerly unknown composition and crystal structure. The investigation of the homogeneous, monophasic, and crystalline powder was performed using X‐ray (23 ?C) and neutron (–271.5 ?C) diffraction methods. The structure solution led to an unusual arrangement of boron atoms, characterized by two different types of polyhedra, a distorted pentagonal bipyramid and a distorted octahedron. The Rietveld refinement of the crystal structure was carried out in the orthorhombic space group Cmmm (X‐ray: a = 18.6945(6) Å, b = 5.7009(2) Å, c = 4.1506(1) Å, V = 442.35(1) Å3, Z = 2; Rwp = 0.087, Rp = 0.067).  相似文献   

10.
Hochtemperatur‐Cs2[PdCl4] — New Results on a “wellknown” Compound Two modifications of Cs2[PdCl4] have been characterized by X‐ray powder and single crystal diffraction, respectively. The crystal structures are described and the group‐subgroup‐relations between these structures are discussed. In addition to the tetragonal (P4/mmm (No. 123), a = 7.4158(8) Å, c = 4.6792(6) Å) and the orthorhombic (Cmcm (No. 63), a = 10.529(1) Å, b = 10.310(1) Å, c = 9.460(1) Å) modification DSC investigations and high‐temperature X‐ray diffraction experiments with synchrotron radiation show the existence of another modification or of yet unknown decomposition products. The phase transformation from the orthorhombic to the tetragonal polymorph is completely finished at 100 °C. The second effect is detected at 319 °C.  相似文献   

11.
Cobalt complexes of Co(3Cn)2(MeOH)4, derived from 3,4,5‐trialkyloxybenzoate ligand (noted as 3Cn) with n = 10, 12, 14 and 16, were synthesized and characterized. The crystal of Co(1C12)2(MeOH)4 were determined by means of x‐ray single crystal analysis. It crystallizes in the monoclinic P21/c space group with a = 24.3271(19) Å, b = 14.0058(11) Å, c = 6.4612(4) Å, α = γ = 90o, β = 94.368(4)o, and Z = 2. The phase texture and mesogenic properties were detected by polarized optical microscopic and powder x‐ray diffraction technique. It was found that these compounds display the cubic phases. Differential scanning calorimetric data indicated that these compounds were nearly room temperature liquid crystalline and with a very wide mesogenic phase range.  相似文献   

12.
The compounds Li8EN2 with E = Se, Te were obtained in form of orange microcrystalline powders from reactions of Li2E with Li3N. Single crystal growth of Li8SeN2 additionally succeeded from excess lithium. The crystal structures were refined using single‐crystal X‐ray diffraction as well as X‐ray and neutron powder diffraction data (I41md, No. 109, Z = 4, Se: a = 7.048(1) Å, c = 9.995(1) Å, Te: a = 7.217(1) Å, c = 10.284(1) Å). Both compounds crystallize as isotypes with an anionic substructure motif known from cubic Laves phases and lithium distributed over four crystallographic sites in the void space of the anionic framework. Neutron powder diffraction pattern recorded in the temperature range from 3 K to 300 K and X‐ray diffraction patterns using synchrotron radiation taken from 300 K to 1000 K reveal the structural stability of both compounds in the studied temperature range until decomposition. Motional processes of lithium atoms in the title compounds were revealed by temperature dependent NMR spectroscopic investigations. Those are indicated by significant changes of the 7Li NMR signals. Lithium motion starts for Li8SeN2 above 150 K whereas it is already present in Li8TeN2 at this temperature. Quantum mechanical calculations of NMR spectroscopic parameters reveal clearly different environments of the lithium atoms determined by the electric field gradient, which are sensitive to the anisotropy of charge distribution at the nuclear sites. With respect to an increasing coordination number according to 2 + 1, 3, 3 + 1, and 4 for Li(3), Li(4), Li(2), and Li(1), respectively, the values of the electric field gradients decrease. Different environments of lithium predicted by quantum mechanical calculations are confirmed by 7Li NMR frequency sweep experiments at low temperatures.  相似文献   

13.
《Solid State Sciences》2001,3(6):677-687
Partial substitution of P by As, leading to the solid solution CsH2(PO4)1−x(AsO4)x, with x=0.28 (abbreviated as CDAP) has been shown. The structural characteristics of the crystals were analyzed by means of X-ray diffraction, which revealed that the new title compound is nearly isomorphous with the monoclinic phase of CsH2PO4 (CDP). The structure was solved from 796 independent reflections with R1=0.0292 and Rw2=0.0702, refined with 59 parameters. The following results have been obtained: space group P21, a=4.9250(4) Å, b=6.4370(3) Å, c=7.9280(6) Å, β=107.316(3)°, V=239.94(3) Å3, Z=2 and ρcal=3.349 g cm−3. The hydrogen bonds are clearly distinguished in the electron density maps which display distributions corresponding to order of protons. The shorter bond (2.452(4) Å), links the phosphate–arsenate groups into chains running along the b-axis and the longer bond (2.531(3) Å), crosslinks the chains to form (001) layers. The Raman and infrared spectra of CDAP recorded at room temperature in the frequency ranges 15–1200 cm−1 and 400–4000 cm−1, respectively, confirm the presence of PO3−4 and AsO3−4 groups in the crystal. Differential scanning calorimetry traces show three phase transitions at 333, 449 and 490 K in this material, which are characterized by X-ray powder diffraction at high temperature.  相似文献   

14.
The compound Na3MoO4F was synthesized by high temperature solution methods. Single‐crystal X‐ray diffraction analysis reveals that Na3MoO4F crystallizes in the orthorhombic space group Pnma (No. 62) with lattice constants a = 5.588(2) Å, b = 7.515(3) Å, c = 12.876(5) Å, and Z = 4. The crystal structure consists of isolated MoO4 groups and [FNa3] chains, which are connected by Na–O bonds to form a three‐dimensional framework. A detailed structure comparison between Na3MoO4F and NaMoO3F was carried out. IR spectroscopy and bond valence sum analysis of Na3MoO4F indicate that the structure is reasonable. In addition, the electronic structure was investigated by the first‐principles method.  相似文献   

15.
A new metal borophosphate PbII4{Co2[B(OH)2P2O8](PO4)2}Cl ( 1 ), containing both Pb2+ cations and Cl anions, was hydrothermally synthesized and characterized by powder X‐ray diffraction, ICP, TG/DTA, and FTIR spectroscopic analyses. The crystal structure determination from single‐crystal X‐ray diffraction reveals that compound 1 crystallizes in the trigonal space group R c (No. 167), a = 9.7513(7) Å, c = 91.060(13) Å, V = 7498.7(13) Å3 and Z = 18. Its structure features a new cobalt borophosphate layer {Co2[B(OH)2P2O8](PO4)2}7– built up from CoO5 square pyramids, [B(OH)2P2O8]5– borophosphate trimers and PO4 tetrahedra. Extra‐framework Pb2+ and Cl ions are located at the vacancy of layers to achieve the charge neutrality of the framework. Magnetic measurements indicate that antiferromagnetic interactions exist between Co2+ ions with a negative Weiss constant of –20.3 K.  相似文献   

16.
For the Ti/O system, three titanium monoxide (TiO) phases (α, β, and γ) with defective NaCl‐type structures and a high‐temperature hexagonal phase (H) have been known for decades. In this work, single crystals of a novel polymorph, ɛ‐TiO, were synthesized by using a bismuth flux. X‐ray diffraction (XRD) revealed a hexagonal crystal structure (a=4.9936(3) Å, c=2.8773(2) Å, P 2m) that is isotypic with ɛ‐TaN. While the Ti atoms are surrounded by trigonal prismatic (sixfold coordination) and trigonal planar (threefold coordination) arrangements of O atoms, the O atoms are found in a pseudo‐square‐pyramidal arrangement of Ti atoms. First‐principles calculations of the formation enthalpy and the electron and phonon density of states and crystal orbital Hamilton population (COHP) analysis revealed that ɛ‐TiO is more stable than α‐TiO, which had previously been regarded as the most stable phase at low temperatures.  相似文献   

17.
《Solid State Sciences》2012,14(9):1355-1360
Single crystals of K2[Co(1−x)Nix(H2O)6] (C8H5O4)4·4H2O (x = 0.25) (PCNHP), a semiorganic black colored transparent crystal of size ∼20 × 13 × 4 mm3, are grown from an aqueous solution of potassium hydrogen phthalate enriched with cobalt chloride and nickel chloride by slow evaporation solution growth technique at room temperature. Structural analysis by single crystal X-ray diffraction reveals that the crystal belongs to monoclinic system with space group P21/c and the cell parameters are a = 10.41(3) Å, b = 6.84(2) Å, c = 29.46(9) Å, Z = 4. Incorporation of both Co(II) and Ni(II) into the potassium hydrogen phthalate (KHP) crystal lattice is well confirmed by EDS and chemical tests. Powder XRD profiles indicate the crystallinity and FT-IR studies reveal the vibrational patterns. The UV–vis optical absorption spectrum of PCNHP shows the lower optical cut-off at ∼300 nm and the crystal was transparent in the entire visible region. The crystalline perfection of the grown crystal analysed by high-resolution X-ray diffraction (HRXRD) analysis reveals that the diffraction curve (DC) contains multi-peaks with low angular spread indicating the possibility of low angle structural grain boundaries. Scanning electron microscope (SEM) studies indicate the structure defect centers. The dielectric, thermal and mechanical behaviors of the specimen were also investigated.  相似文献   

18.
Two ternary borides MNi9B8 (M=Al, Ga) were synthesized by thermal treatment of mixtures of the elements. Single‐crystal X‐ray diffraction data reveal AlNi9B8 and GaNi9B8 crystallizing in a new type of structure within the space group Cmcm and the lattice parameters a=7.0896(3) Å, b=8.1181(3) Å, c=10.6497(4) Å and a=7.0897(5) Å, b=8.1579(4) Å, c=10.6648(7) Å, respectively. The boron atoms build up two‐dimensional layers, which consist of puckered [B16] rings with two tailing B atoms, whereas the M atoms reside in distorted vertices‐condensed [Ni12] icosahedra, which form a three‐dimensional framework interpenetrated by boron porphyrin‐reminiscent layers. An unusual local arrangement resembling a giant metallo‐porphyrin entity is formed by the [B16] rings, which, due to their large annular size of approximately 8 Å, chelate four of the twelve icosahedral Ni atoms. An analysis of the chemical bonding by means of the electron localizability approach reveals strong covalent B?B interactions and weak Ni?Ni interactions. Multi‐center dative B?Ni interaction occurs between the Al–Ni framework and the boron layers. In agreement with the chemical bonding analysis and band structure calculations, AlNi9B8 is a Pauli‐paramagnetic metal.  相似文献   

19.
Four new macrocyclic dinuclear dibutyltin(IV) dithiocarbamate complexes of the type [Bu2Sn(dtc)]2, where dtc = hexane‐1,6‐diylbis(4‐fluorobenzyldithiocarbamate) anion ( 1 ), hexane‐1,6‐diylbis(4‐chlorobenzyldithiocarbamate) anion ( 2 ), hexane‐1,6‐diylbis(furfuryldithiocarbamate) anion ( 3 ) and hexane‐1,6‐diylbis(pyrrole‐2‐ylmethyldithiocarbamate) anion ( 4 ), have been prepared. The dithiocarbamate ligands efficiently self‐assemble with Bu2Sn(IV) to form bimetallic 26‐membered macrocycles. All the complexes have been characterized using elemental analysis, infrared and NMR (1H and 13C) spectroscopies and X‐ray crystallography. Single‐crystal X‐ray diffraction analysis of all the complexes confirms the formation of the dinuclear metallomacrocycles in which dithiocarbamate ligands are asymmetrically bound to the tin atoms. The coordination sphere around the tin atom in 1 – 4 can be described as a skew trapezoidal bipyramid. The dimensions of the cavity of the macrocycles of 1 – 4 are ca 8.0 × 9.0 Å2. Complexes 1 – 4 were evaluated for their in vitro anticancer activity against MCF‐7 and HL‐60 cells. Complexes 1 and 2 are more active against MCF‐7 and HL‐60. Thermal decomposition of 1 and 4 yielded tin sulfides. They were characterized using powder X‐ray diffraction (PXRD), high‐resolution transmission electron microscopy and UV diffuse reflectance and energy‐dispersive X‐ray spectroscopies. PXRD studies reveal that the as‐prepared tin sulfides are composed of orthorhombic phase of SnS.  相似文献   

20.
Dimethylammonium trifluoromethanesulfonate 1 was synthesized by reaction of trifluoromethanesulfonic acid with an excess of dimethylamine. A temperature variable synchrotron measurement on the polycrystalline substance reveals that 1 passes through a phase transition below room temperature. The transition occurs in the temperature range of 282–285 K on heating and 272–280 K on cooling as determined by DSC. The room temperature phase crystallizes in space group Cmca (a = 11.031(6) Å, b = 18.466(14) Å, c = 8.173(9) Å, V = 1665(2) Å3, Z = 8) and the low temperature phase in space group P 21/c (a = 8.8717(18) Å, b = 8.0838(16) Å, c = 10.968(2) Å, β = 92.128(4)°, V = 786.0(3) Å3, Z = 4). The structures of both phases were determined by single crystal X‐ray diffraction, but refinement did not yield satisfactory residuals for the low temperature phase because of twinning of the crystal. It was, therefore, independently solved from the synchrotron powder diffraction data using rigid body models of the constituent ions and ab‐initio direct space methods. Both, the CF3 group and the SO3 group of the triflate ion, are rotationally disordered around the S–C bond, in the room temperature phase. In the low temperature phase, the triflate ion is well localized. Like in the alkali metal triflates, the triflate ions are arranged in double layers with the hydrophobic trifluoromethyl groups and the sulfonate groups, respectively, pointing towards each other. The dimethylammonium ion is located closer to the sulfonate group with contacts indicating hydrogen bonding. The packing in both phases is of the topological CsCl structure type.  相似文献   

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