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1.
The structure of 2-({[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methyl} sulfonyl)-1H-1,3-benzimidazole, C16H14N3O3F3S, has been solved. The compound belongs to the monoclinic space group (P21/c) with cell parameters a = 8.8693(9) Å, b = 23.369(2) Å, c = 8.6141(8) Å, β = 104.68(1)°, V = 1727.2(3) Å3, Z = 4. The final R and wR(F 2) values were 0.070 and 0.147, respectively. The title molecule has a ‘Z’ shape in the crystal structure. The fused benzimidazole moiety and the pyridine ring are nearly coplanar. The molecules are linked by N-H…N and C-H…O hydrogen bonds into chains of edge-fused R 2 2 (14), R 2 2 R 2 2 (8), and R 2 2 (18) rings along the c-axis. The crystal lattice is further strengthened by π-π stacking interactions.  相似文献   

2.
Two nickel (imidazole) complexes, Ni(im)6Cl2·4H2O (1) and Ni(im)6(NO3)2 (2) (im=imidazole) have been synthesized and characterized by elemental analysis, IR, UV, TG and single crystal X-ray diffraction. 1 crystallizes in the triclinic space group P-1 with a=8.800(6) Å, b=9.081(6) Å, c=10.565(7) Å, =75.058(9)°, β=83.143(8)°, γ=61.722(8)°, V=718.3(8) Å3, Z=1 and R1 (wR2)=0.0469 (0.1497). 2 crystallizes in the trigonal space group R-3 with a=12.370(6) Å, b=12.370(6) Å, c=14.782(14) Å, =90.00°, β=90.00°, γ=120.00°, V=1959(2) Å3, Z=3 and R1 (wR2)=0.0358 (0.0955). 1 and 2 exhibit different supramolecular network due to their different counter anions and different hydrogen bonding connection. In compound 1, [Ni(im)6]2+ cation and counter anions Cl alternatively array in an ABAB fashion via N–HCl hydrogen bonding. In compound 2, the plane of each NO32− is almost parallel and each NO32− connect three different [Ni(im)6]2+ cations via N–HO hydrogen bonding.  相似文献   

3.
Six diorganotin esters of Schiff-base ligands formulated as [R2SnLY]2, where L1 is C6H5CON2C(CH3)CO2 with Y?=?CH3CH2OH, R?=?mClC6H4CH2 (1), oFC6H4CH2 (2), pFC6H4CH2 (3) and L2 is 2-HOC6H4CON2C(CH3)CO2 with Y?=?CH3OH, R?=?oFC6H4CH2 (4), pFC6H4CH2 (5), mClC6H4CH2 (6) have been prepared and characterized by elemental analysis, IR, 1H and 119Sn NMR spectra. The crystal structures of complexes 1 and 4 have been determined by X-ray single crystal diffraction. The structure analyses reveal that the Sn atom in both 1 and 4 is seven-coordinate in distorted pentagonal bipyramid geometries with a planar SnO4N unit and two apical aryl carbon atoms, thus forming a dimeric molecule, which sits on a crystallographic center of symmetry. Intramolecular or intradimeric hydrogen bonds contribute to the stability and compactness of the crystal structures.  相似文献   

4.
A new ternary indide La8Co2In3 was prepared by arc-melting of the compact metals under an argon atmosphere. A subsequent high temperature treatment was used for single crystal growth. The crystal structure has been determined from X-ray single crystal data: own structure type, space group Pmn21, Pearson code oP26, Z = 2, a = 10.2646(11), b = 10.1802(12), c = 7.3235(8) Å, R1 = 0.0338, wR2 = 0.0458, for 1556 independent reflections with I > 2σ(I) and 71 variables. Similarly to intermetallic compound with a high rare earth content, atoms in the title structure have no high coordination numbers: 12–15 for lanthanum, 9 and 7 for cobalt, and 11 for indium. Strong Co–Co bonding is observed in the structure. The packing of In polyhedra can be represented as a complicated variant of the RuB2 structure type.  相似文献   

5.
A ternary boride Ga2Ni21B20, with modified Zn2Ni21B20-type structure (space group I4/mmm, and lattice parameters a = 7.2164(1) Å, c = 14.2715(4) Å), was synthesized from the constituent elements. Single crystal diffraction data reveal Ni at 8f site splitting into 16m position with nearly half occupancy. In this structure, [Ni6B20] cages share ligand boron atoms with [Ga2B4Ni9] hexa-capped square prisms, forming two dimensional layers. Layers are interconnected via Ga−Ni interactions and build up a three-dimensional framework. Quasi-two-dimensional infinite planar nets formed by intercrossed Ni atoms are embedded. Ga2Ni21B20 is a metallic Pauli paramagnet, in agreement with electronic structure calculations, resulting in 8.2 states eV−1 f.u−1 at the Fermi level.  相似文献   

6.
The reaction of grossmisin (8α-hydroxyachillin,1) with chlorine in benzene afforded a mixture of products. The less polar product readily crystallized after chromatography. According to the X-ray diffraction data, this product has the structure of 1α,10β-dichloro-1,10-dihydrogrossmisin. The second chloro derivative of grossmisin,viz., 8β-chloroachillin, was prepared in good yield by the reaction of lactone1 with PCl5 in CHCl3 in the presence of Py. Published inIzvestiya Akademii Nauk Seriya Khimicheskaya, No. 11, pp. 1932–1934, November, 2000.  相似文献   

7.
Two new complexes, {[Pr(2-IBA)3?·?2,2′-bipy]2·[Pr(2-IBA)3?·?2,2′-bipy]2?·?0.5C2H5OH?·?H2O} (1) and [Pr(2-IBA)3?·?phen]2 (2) (2-IBA?=?2-iodobenzoate; 2,2′-bipy?=?2,2′-bipyridine; phen?=?1,10-phenanthroline) were synthesized, and their crystal structures were determined by X-ray diffraction. Complex 1 consists of two binuclear molecules [Pr(2-IBA)3?·?2,2′-bipy]2 (a) and [Pr(2-IBA)3?·?2,2′-bipy]2 (b), half uncoordinated ethanol and one uncoordinated water. In the two molecules (a) and (b), the coordination environment of central ions is similar. The Pr13+ ion in molecule (a) and Pr23+ ion in molecule (b) are nine-coordinate with seven oxygen atoms from five 2-IBA ligands and two nitrogen atoms from one 2,2′-bipy molecule. The crystal structure of complex 2 is similar to that of binuclear [Pr(2-IBA)3?·?2,2′-bipy]2 in complex 1.  相似文献   

8.
Single crystals of NaCoO2 have been successfully synthesized for the first time by a flux method at 1323 K. A single-crystal X-ray diffraction study confirmed the trigonal space group and the lattice parameters , . The crystal structure has been refined to the conventional values R=1.9% and wR=2.1% for 309 independent observed reflections. The electron density distribution of NaCoO2 has been studied by the maximum entropy method (MEM) using single-crystal X-ray diffraction data obtained at 298 K. From the results of the MEM analysis, the strong covalent bonding was clearly observed between Co and O atoms, while no bonding was observed around Na atoms. We also calculated the electron density of NaCoO2 by first principles calculations. The electron density obtained experimentally is in good agreement with the theoretical one.  相似文献   

9.
Reaction of BiCl3 with one equivalent of 2,4,6-triphenylphenyllithium in toluene results in the formation of crystalline 2,4,6-triphenyl-phenylbismuthdichloride toluene disolvate (1). The crystal structure of 1 has been determined by X-ray diffraction. In spite of the extremely bulky substituents at the bismuth atom, complex 1 is dimeric in the solid state with intramolecular Bi-Cl bond lengths of 2.530(1) Å and bridging Bi-Cl of 3.074(1) Å.  相似文献   

10.
The new phase Ir13Al45 was synthesized in equilibrium with an aluminum-rich melt. Its crystal structure was established from single-crystal diffraction data. The compound crystallizes in the space group Pnma and represents a novel structure type (Pearson symbol oP232, a=16.760(2) Å, b=12.321(1) Å, c=17.425(2) Å). The structure can essentially be described as a simple hexagonal column packing of pseudopentagonal columns formed by irregular Al polyhedra centered by Ir atoms. Ir13Al45 forms peritectically at 895 °C and exists in equilibrium with the melt in a narrow temperature interval of 19 °C.  相似文献   

11.
Accurate profile analysis of X-ray diffraction data was carried out to settle recent dispute on the symmetry and crystal structures of the double perovskite Ba2LaIrO6. Even through careful comparison of the full-width at half-maximum values, we found no evidence for Ba2LaIrO6 adopting either monoclinic (I2/m) or mixed rhombohedral and monoclinic (I2/m) structures at room temperature, becoming triclinic at below about 200 K. The correct space group is just at temperatures between 82 and 653 K. Furthermore, the phase transition does occur in Ba2LaIrO6, but the transition temperature is found to be much higher than the reported value.  相似文献   

12.
New members of the AnBn−1O3n perovskite-like family (Ba5KNb5O18 and Sr6Nb4SnO18 compounds) with n = 6 have been synthesized and studied by the X-ray powder diffraction. Their crystal structures were found to belong to the Ba6Nb4TiO18-type with a = 0.57840(7) nm, c = 4.2532(5) nm and a = 0.5661(1) nm, c = 4.186(1) nm for Ba5KNb5O18 and Sr6Nb4SnO18, respectively. It was shown that Ba and K (A-atoms) are completely disordered in the crystal structure of Ba5KNb5O18 compound. But Nb and Sn atoms (B-atoms) in the crystal structure of the Sr6Nb4SnO18 compound are quite ordered with the preferred Sn+4 and Nb5+ cations localization in the center of perovskite-like block and on the boundaries of these blocks, respectively. Temperature and frequency dependencies of the real components of electric conductivity σI and dielectric permeability ɛI; specific electric conductivity at the direct current σdc have been obtained by the impedance spectroscopy method for Sr6Nb4SnO18.  相似文献   

13.
The crystal structure of 3-methyluracil has been determined ab initio by conventional monochromatic X-ray powder diffraction data. The crystal data are: orthorombic, a=6.6294(1), b=13.1816(3), c=6.53938(9) (Å), V=571.45(3) (Å3), space group Pbnm, Z=8. The structure was solved by direct methods and the final Rietveld refinement converged to Rp=0.0398, Rwp=0.0528, RBragg=0.0294. The crystal structure exhibits endless chains of planar molecules, connected via head-to-tail N-H?O hydrogen bonds.  相似文献   

14.
A simple one-step synthesis of 2,6-dimethylanthracene, 1, in high yield is reported utilizing the easily accessible benzyl alcohol as the starting material. Based on 2,6-dimethylanthracene, two pseudo-triptycene compounds, cis-2,6-dimethyl-9,10-dihydroanthracene-9,10-endo-α,β-succinic anhydride, 2, and cis-2,6-dimethyl-9,10-dihydroanthracene-9,10-endo-α,β-succinyl amine, 3, are firstly synthesized in high yield and they are characterized by single crystal X-ray diffraction. Compound 2 crystallizes in triclinic space group and compound 3 crystallizes in monoclinic P21/c space group. Both compound 2 and 3 exhibit cis-configurations and endo-conformations. Compound 1 exhibits very intense photoluminescence property due to the delocalized electron in the whole molecule, whereas fluorescence quench happens to some extents due to the destruction of the conjugated structure in compound 2.  相似文献   

15.
The reaction of diethanolamine with diferrocenylmethyl carbonium (2) that was generated by diferrocenylmethanol (1) treated with BF3 in CH2Cl2 provided the synthesis of title compound diferrocenylmethoxyethylamine (3). The structure of 3 was determined by the X-ray diffraction (XRD) with crystal data: monoclinic P21/n space group and a=5.8419(14) Å, b=13.572(3) Å, c=23.839(6) Å, α=90°, β=91.827(5)°, γ=90°, V=1889.2(8) Å3, Z=4, D c =1.558 mg·m?3, μ=1.548 mm?1, F(000)=920. The intra- and inter-molecular H bonding modes in 3 were demonstrated both in molecular crystal structure and IR spectral characterization.  相似文献   

16.
Phase relations in the Sr-Fe-Co-O system have been investigated at 1100 °C in air by X-ray powder diffraction on quenched samples. Solid solutions of the form SrFe1−xCoxO3−δ (0?x?0.7), Sr3Fe2−yCoyO7−δ (0?y?0.4) and Sr4Fe6−zCozO13±δ (0?z?1.6) were prepared by solid-state reaction and by the sol-gel method. The structural parameters of single-phase samples were refined by the Rietveld profile method. The variation of the lattice parameters with composition has been determined for each solid solution and a cross-section of the phase diagram at 1100 °C in air for the entire Sr-Fe-Co-O system has been constructed.  相似文献   

17.
Three new silver indium double phosphates Ag3In(PO4)2 (I), β-(II) and α-Ag3In2(PO4)3 (III) were synthesized by solid state method (I and II—700 °C, III—900 °C). Compounds I and II crystallize into a monoclinic system (I—sp. gr. C2/m, Z=2, a=8.7037(1)Å, b=5.4884(1)Å, c=7.3404(1)Å, β=93.897(1)°; II—sp. gr. C2/c, Z=4, a=12.6305(1)Å, b=12.8549(1)Å, c=6.5989(1)Å, β=113.842(1)°), and compound III crystallize into a hexagonal system (sp. gr. R-3c, Z=6, a=8.9943(1)Å, c=22.7134(1)Å). Their crystal structures were determined by the Rietveld analysis (I—Rp=6.47, Rwp=8.54; II—Rp=5.67, Rwp=6.40; III—Rp=7.30, Rwp=9.91). Structure of Ag3In(PO4)2 is related to the sodium chromate structure type and is isotypic to α-Na3In(PO4)2. The polymorphous modifications of β- and α-Ag3In2(PO4)3 are isostructural to sodium analogs (β- and α-Na3In2(PO4)3) and are related to alluaudite (II) and NASICON (III) structure types. Compounds I and II are not stable at temperature above 850 °C. Ag3In(PO4)2 is decomposed providing silver orthophosphate Ag3PO4 and α-Ag3In2(PO4)2. β-Ag3In2(PO4)3 is transformed to α-Ag3In2(PO4)3.  相似文献   

18.
Eight new antimony (III) complexes containing dithiocarbamate ligands (R2NCS2)2SbBr [R2NCS2 = OC4H8NCS2 (1), C2H5NC4H8NCS2 (2), Me2NCS2 (3), C4H8NCS2 (4)] and (R2NCS2)3Sb[R2NCS2 = C5H10NCS2 (5), Bz2NCS2 (6), Et2NCS2 (7), (HOCH2CH2)2NCS2 (8)] have been synthesized by the reactions of antimony (III) halides with dithiocarbamate ligands in 1:2 or 1:3 stoichiometries. All the complexes have been characterized by elemental analysis, melting point as well as spectral [IR and NMR (1H and 13C)] studies. The crystal structures of complexes 1, 5 and 8 have been determined by X-ray single crystal diffraction, and their electrochemical character has also been studied.  相似文献   

19.
The negative hyperconjugation (NHC) of sp2 and sp3 hybrid nitrogen atoms were studied based on the calculation of quinoxaline derivatives containing piperazine moiety. The energy level, electronic density and spatial position of acceptor orbital are all important factors of NHC. NHC of nitrogen atom does not limit in the case that the σ*-acceptor orbital is in the anti-staggered positon of donor orbital, but it will switch off when nitrogen atom loses its lone pair electron. These results are proved by the crystal structure and the calculation of vibration frequencies. At last, two quinoxaline derivatives synthesized in this work show good anticancer activities against leukemia cell lines.  相似文献   

20.
In order to develop novel oligothiophene-based liquid crystals capable of hydrogen bonding, new terthiophene derivatives containing an alkylamide group, N,N′-dialkyl-5,5″-dichloro-2,2′:5′,2″-terthiophene-4,4″-dicarboxamide (DNCnDCl3T, n=8, 18), N,N′-dialkyl-5,5″-dibromo-2,2′:5′,2″-terthiophene-4,4″-dicarboxamide (DNCnDBr3T, n=5, 8, 16, 18), or N,N′-dialkyl-5,5″-diiodo-2,2′:5′,2″-terthiophene-4,4″-dica-rboxamide (DNCnDI3T, n=8, 18), were designed and synthesized, and their thermal behaviour was examined. It was found that DNC18DCl3T, DNC18DI3T and DNCnDBr3T (n=8, 16, 18) form a smectic A phase and that the alkyl chain length greatly affects liquid crystal phase formation. The absence of liquid crystallinity in the corresponding ester derivatives suggests that intermolecular hydrogen bonding also plays a role in the formation of a liquid crystal phases in the DNCnDBr3T system.  相似文献   

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