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1.
Crystallography Reports - The crystal structure of the title compound is determined by single crystal X-ray structure analysis. The structure was solved by direct method and refined to a final...  相似文献   

2.
本文采用升华法沿着垂直于c轴方向的[1-100]方向生长6H-SiC单晶.利用光学显微镜对晶体表面及腐蚀后的晶片进行观察,发现沿[1-100]方向生长出的单晶与传统方法沿[0001]方向生长单晶有很多的不同之处,多型对于籽晶的继承性非常强,但是在生长过程中多型夹杂不会发生,该方法生长的晶体中没有发现螺位错(微管)缺陷.  相似文献   

3.
The crystal structure of 9–(1,1-dimethyl–2-propenyl)-4-hydroxy-7H-Furo-[3,2-g]-benzopyran-7-one has been determined from X-ray diffraction data. The compound crystallizes in the monoclinic space group C2/c with unit cell parameters a = 8.976(3) Å, b = 16.621(2) Å, c = 17.818(2) Å, β = 95.79(2) Å. The gross structure was determined by direct methods and refined to a final value of R = 0.053. The three ring framework of the molecule is nearly planar. The side chain attached at the atomic position C(9) possesses significant foldings and has been found inclined to the ring system of the molecule.  相似文献   

4.
The X-ray single crystal structure of C13H12O2 compound was determined. It crystallizes in the orthorombic space group P212121 with a = 7.8847(7), b = 9.639(1), c = 13.432(2) Å, Z = 4 and V = 1020.8(3) Å3. The final R converged to 0.037 for 1763 independent reflexions. The title compound forms layers parallel to (1 0 0) planes and the three dimensional cohesion of the crystal is assumed by Van der Waals interactions. The molecule consists of two six-membered rings (A and B) and a seven-membered ring (C). A and B rings are planar, whereas the C ring has a chair conformation  相似文献   

5.
The crystal structure of the title compound C14H12N4OS was determined by the X-ray diffraction method. The compound crystallizes in the triclinic space group $P\bar 1$ with Z = 2. The molecule is not planar: the dihedral angle between the triazole and thiophene rings is 73.98(2)°, and that between the triazole and benzene rings is 4.05(2)°. The thiophene ring is disordered over two positions, which are approximately parallel and oppositely oriented. The major component refined to a site-occupancy factor of 0.573(3). An intramolecular C-H...O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked together by two pairs of N-H...O interactions (to the same O atom as acceptor), forming inversion dimers. The crystal packing is also stabilized by π-π interactions [centroid-centroid distance is 3.978 Å].  相似文献   

6.
Wang  C.  Cheng  S. Y.  Zhao  W. W.  Yang  X. N.  Zhou  K. Z.  Tian  J. J.  Jiang  D. F.  Ma  P. H. 《Crystallography Reports》2020,65(7):1156-1160
Crystallography Reports - This paper reports on the supramolecular self-assembly of cyclopentano cucurbit[5]uril (CyP5Q[5]), L-phenylalanine (L-Phe), and cadmium ions. The crystal structure is...  相似文献   

7.
The cobalt(II) and nickel(II) nitrate complexes with an island structure (Na2[Co(NO3)4] (I) and K2[Co(NO3)4] (II)] and a chain structure [Ag[Co(NO3)3] (III) and K2[Ni(NO3)4] (IV)] are synthesized and investigated using X-ray diffraction. In the anionic complex [Co(NO3)4]2? of the crystal structure of compound I, the Co coordination polyhedron is a twisted tetragonal prism formed by the O atoms of four asymmetric bidentate nitrate groups. In the anion [Co(NO3)4]2? of the crystal structure of compound II, one of the four NO3 groups is monodentate and the other NO3 groups are bidentate (the coordination number of the cobalt atom is equal to seven, and the cobalt coordination polyhedron is a monocapped trigonal prism). The crystal structures of compounds III and IV contain infinite chains of the compositions [Co(NO3)2(NO3)2/2]? and [Ni(NO3)3(NO3)2/2]2?, respectively. In the crystal structure of compound III, seven oxygen atoms of one monodentate and three bidentate nitrate groups form a dodecahedron with an unoccupied vertex of the A type around the Co atom. In the crystal structure of compound IV, the octahedral polyhedron of the Ni atom is formed by five nitrate groups, one of which is terminal bidentate. The data on the structure of Co(II) coordination polyhedra in the known nitratocobaltates are generalized.  相似文献   

8.
The crystal structure of the title compound (PIP) has been determined by single crystal X-ray diffraction methods. C19H12N4. C2H5OH crystallizes in the monoclinic space group P21/n with a = 11.4414(8), b = 12.6052(9), c = 12.4627(8) Å, β = 100.345(2)°, Z = 4, V = 1768.17 Å3, Dcal = 1.286 Mg. m−3, μ (MoKα) = 0.80 cm-1, F(000) = 720. The structure was solved by the direct methods and refined by full-matrix least-squares method to a final R = 0.0337 and Rw = 0.0332 for 2306 reflections with F0 > 4σ(F0). The phenl ring and the imidazo[f]1,10-phenanthroline moiety are coplanar in the crystal. The packing of the molecules involves hydrogen bonded association of the hydroxyl group of ethanol both with the N H of the imidazole moiety of one PIP and one nitrogen atom of the phenanthroline moiety of another PIP.  相似文献   

9.
The crystal structure of [Cu(pyrimidine)4]2BF4 was determined using single crystal X-ray diffraction. The compound crystallizes in the monoclinic space groupP21/n, with lattice parametersa=9.9736(8),b=13.872(1),c=16.568(1) Å. β=98.002(1), andZ=8, yielding a calculated density of 1.857 g/cm3. The Jahn-Teller distorted copper coordination sphere is composed of the four pyrimidine ligands in the equatorial positions (ave. Cu?N=2.02 Å) and the longer axial bonds from the copper to one fluorine (ave Cu?F=2.39 Å) on each of the BF 4 ? anions. The crystal structure features layers of molecules having interleaved pyrimidine rings: the layers are connected through intermolecular H … F hydrogen bonds.  相似文献   

10.
NaBH4 reduction of a cage dione proceeds in a stereospecific fashion to give theendo,endo-diol. This reactivity is related to the crystal structure.  相似文献   

11.
The crystal structure of the potassium tris[3-(2-pyridyl)pyrazolyl]hydroborate has been determined. Potassium tris[3-(2-pyridyl)pyrazolyl]hydroborate crystallizes in the orthorhombic space group Pca21 with the parameters a=30.7323(5) ?, b=8.3083(1) ? and c=9.2173(2) ?, V=2353.48(7) ?3 with Z=4. The crystal structure reveals the formation of continuous chains where two bidentate arms of the hydroborate ligand are coordinated to one potassium and the third to another cation. The structures of numerous transition metal and actinide salts have been reported during the last decades but no alkali metal complexes were available.  相似文献   

12.
4-(E)-2-[3-(3-[(E)-2-(4-Cyanophenyl)-1-diazenyl]perhydrobenzo[d]imidazol-1-ylmethyl) perhydrobenzo[d]imidazol-1-yl]-1-diazenylbenzonitrile (1) has been synthesized by reac- tion of p-cyanobenzene diazonium chloride with a mixture of formaldehyde and trans-1,2-cyclohexanediamine. The crystal structure has been determined by single crystal X-ray diffraction analysis. The bis-triazene (1) does not adopt a folded conformation, unlike previously studied ethylenediamine analogues, and there is no indication of -stacking in the crystal packing. The dominant interaction between molecules is the van der Waal's attraction between cyclohexane rings. This result establishes the structure of the product of this diazonium coupling reaction as the 1-(1-imidazolidinylmethyl)imidazolidine derivative and not the alternate tetraazabicyclo[4.4.1]undecane derivative. Crystal data: 1 C29H34N10, orthorhombic, space group Pbca, a = 17.946(1), b = 13.106(1), c = 24.108(1) Å, V = 5670.6(3) Å3, for Z = 8.  相似文献   

13.
Abstract  The crystal structure of the title compound, C64H70N4O4, has been determined by single crystal X-ray diffraction methods. The title compound crystallizes in the monoclinic space group P2(1)/c with cell dimensions a = 13.8946(3) ?, b = 16.1069(3) ?, c = 12.1974(2) ?, β = 93.4050(10)°, Z = 2. The porphyrin core to be composed of four pyrrole rings linked through methane carbon bridges. Each molecule lies across a crystallographic inversion center. The porphyrin core is planar, which facilitates π-electron delocalization. The inner nitrogen H atoms are found localized on opposite pyrrole rings and these rings differ structurally from the other two pyrrole rings. The imino H atoms form bifurcated intramolecular hydrogen bonds with the adjacent unprotonated N atoms due to the contract porphyrin core. Graphical Abstract  The crystal structure of meso-tetrakis[4-(pentyloxy)phenyl]porphyrin is reported in this paper.   相似文献   

14.
The crystal structure of an asymmetric pentacyclo[5.4.0.02,6.03,10.05,9]undecan-8,11-dione derivative is reported, in which Me3SiCN has been added across one of the keto groups. The cage structure demonstrates the expected effects of this addition.  相似文献   

15.
Abstract  The crystal structure of the title compound, C11H11NOS, was determined by an X-ray diffraction analysis. The compound crystallizes in the monoclinic space group P21/c with cell parameters a = 10.533(2) ?, b = 12.7826(19) ?, c = 7.6491(17) ?, β = 107.997(17)°, V = 979.5(3) ?3 and Z = 4. The S containing heterocycle adopts a sofa conformation, whereas the 5-membered ring adopts an envelope conformation. The crystal packing is characterized by weak C–H···N contacts and π-stacking interactions. Graphical Abstract  The title compound, 3-methyl-3a,4-dihydro-3H-thiochromeno[4,3-c]isoxazol was synthesized by an 1,3 dipolar cycloaddition reaction and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the aromatic 6-membered ring is planar, whereas the ring containing the S atom adopts a sofa conformation and the 5-membered ring an envelope conformation. The methyl group is in an equatorial position.   相似文献   

16.
The crystal structures of three compounds formed via ultimate nucleophilic attack of unsaturated hydrocarbon fragments are reported. Geometries of the bis(vinyl)-, mono(vinyl), and bis(ethynyl)-substituted PCU species are unexceptional. The crystal structures are dictated by the availability of intermolecular hydrogen bonding.  相似文献   

17.
A tetracyanometallate with complex dien cation [Fe(dien)2][Ni(CN)4] (1) (dien = diethylenetriamine), has been prepared and characterized by IR, UV-Vis and ESR spectroscopies. Single crystal X-ray analysis reveals that the compound assumes a ‘zero-dimensional’ structure in which one iron(II) ion is coordinated by six nitrogen atoms of the two dien ligands and the [Ni(CN)4]2− anion remains outside the coordination sphere. The six-coordinate iron(II) centres display a distorted octahedral arrangement.  相似文献   

18.

Abstract  

The crystal growth of (C6H14N2)[Cr2O7], consists of a diazabicyclo[2.2.2]octane-1,4-diium cation and a discrete dichromate anion, in solution has been determined under the influence of various factors. Four factors, which influence the crystal size, crystal growth and nucleation, were chosen. These factors are concentration, temperature, type of solvent and method of crystallization. Taguchi design of experiments (DOE) method has been used for to plan a minimum number of experiments and optimization of crystallization processes. Crystallization of diazabicyclo[2.2.2]octane-1,4-diium dichromate with desirable particle size, shape and minimum time of crystal growth as performance characteristics were studied. The changes in the crystal growth habit were observed and could be explained by the differences in the morphology on the various photograph of this compound.  相似文献   

19.
The title compound C17H14BrFO4 was synthesized using 3-Bromo-4-hydroxy-phenyl-(4-fluoro-phenyl)-methanone, ethyl chloroacetate, and anhydrous potassium carbonate. Its structure was established using elemental analysis, NMR, and single crystal X-ray diffraction techniques. The compound crystallizes in orthorhombic crystal system and space group Pbca. The cell parameters are a = 10.1444(13) Å, b = 8.2781(10) Å, c = 38.423(5) Å, Z = 8, V = 3226.6(7) Å3. The dihedral angle between two least squares planes of two phenyl rings bridged by keto carbonyl group is ?28.2(5)°. The molecule exhibits intermolecular interactions of the type C?H…F and C?H…O. The intercontacts in the crystal structure are studied using Hirshfeld surface analysis.  相似文献   

20.
1-[2-(p-Tolyl)-1-diazenyl]-3-({3-[2-(p-tolyl)-1-diazenyl]perhydrobenzo[d]imidazol-1-yl}methyl)perhydrobenzo[d]imidazole(1) has been synthesized by reactionof a mixture of 1,2-diaminocyclohexane and formaldehyde withp-toluene diazonium chloride inaqueous solution. The product has been characterized by IR and NMRspectroscopy and elemental analysis. A crystal grown from solution ina mixed solvent system of ethyl acetate and hexanes was analyzed byX-ray crystallography. The solution of the crystal structure of(1) is important in establishing theconnectivity of this molecule and other compounds of similarstructure. The crystal structure of (1) is compared with the previously reportedstructure of the p-cyano analogue(2). Compounds (1) and (2)differ principally in the relative orientation of the heterocyclicrings; in (1), the molecule has adistinct V-shape, whereas compound (2) adopts a more extended conformation.Significant conjugation within the triazene moieties is evident inboth (1) and (2), as manifested in the N465=N andN–N bond lengths. The conjugation is greater in (2) due to the extended conjugation through tothe nitrile group. The title compound (1){C29H40N8}crystallizes in the monoclinic, space group C2/c, with lattice constants: a = 30.532(6) ?,b =5.9050(12) ?, c= 15.463(3) ?, α = 90°,β = 99.94(3)°, γ = 90°,V =2746.0(10) ?3, Z = 4, D c =1.209 mg m−3,F(000) = 1076, R 1 = 0.0785,wR 2= 0.1877.  相似文献   

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