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1.
The structure of the [(DCH-6A ? NH4)(H2O)I]2 complex obtained by the reaction between the cis-syn-cisisomer of dicyclohexano-18-crown-6 (DCH-6A) and NH4I has been determined by X-ray diffraction analysis. The crystals are triclinic, a = 9.314(3) Å, b = 11.951(2) Å, c = 12.040(1) Å, α = 77.36(1)°, β = 81.59(1)°, γ = 80.41(2)°, space group $P\bar 1$ , Z = 2, and the final R factor is 0.044. The structure is built up of the (DCH-6A ? NH4) + cationic complexes, iodide anions, and water molecules. The ammonium ion forms three hydrogen bonds of the NH?O type [N?O, 2.881(5)–2.890(5) Å] with the oxygen atoms of the crown ether molecule. The organic cations are joined together into centrosymmetric dimers through the system of hydrogen bonds of the NH?OH type. The I??O distances (where the O atom belongs to the bridging water molecule) fall in the range 3.558(4)–3.610(4) Å.  相似文献   

2.
The molecular and crystal structures of chiral 1R, 4R-cis-2-(4-hydroxybenzylidene)-p-menthan-3-one (I) are determined by X-ray diffraction analysis. Single crystals of I are orthorhombic, a = 8.997(2) Å, b = 11.314(2) Å, c = 14.847(3) Å, V = 1511.3(5) Å3, Z = 4, and space group P212121. The cyclohexanone ring in molecules of compound I has a chair-type conformation with the axial methyl and equatorial isopropyl groups. The enone and benzylidene groupings are nonplanar. The considerable distortion of bond angles at the sp 2 carbon atoms of the benzylidene grouping and the puckering parameters of the cyclohexanone ring in the structure of I are close to those observed for the previously studied compound with the p-methoxy substituent. In the crystal, molecules I are linked by very short intermolecular hydrogen bonds .  相似文献   

3.
Polyphosphates of the compositions LiPO3, Li4H(PO3)5, and LiMn(PO3)3 were prepared by the reactions of Li2CO3 and MnO2 with melts of polyphosphoric acids at 240–350°C, and their crystal structures were established. The unit-cell parameters are a = 13.074 Å, b = 5.4068 Å, c = 16.452 Å, β = 99.00°, sp. gr. P2/n; a = 6.6434 Å, b = 7.253 Å, c = 11.399 Å, α = 72.60°, β = 83.36°, γ = 85.32°, sp. gr.; $P\bar 1$ ; a = 8.364 Å, b = 8.561 Å, c = 8.6600 Å, sp. gr. P212121, respectively. The influence of cations on the structures of the compounds is discussed.  相似文献   

4.
Trichlorotricyanobenzene-mesitylene (1/1) is monoclinic, space group P21/n; at ?88°Ca=10.509(3),b=14.863(7),c=11.518(3) Å, β=99.38(2)0,V=1775(2) Å3,D x =1.409(2) g cm?3,Z=4. Trichlorotricyanobenzene-benzene (1/3) is hexagonal, space group $P\bar 6$ ; at ?99°Ca=17.3914(3),c=7.2673(1) Å,V=1903.6(1) Å3,D x =1.2844(1) g cm?3,Z=3. In both complexes there are stacks of alternating trichlorotricyanobenzene and hydrocarbon molecules. In both complexes there are sheets of molecules perpendicular to the stacks. In the mesitylene complex these sheets contain equal numbers of both kinds of molecules with the trichlorotricyanobenzene molecules arranged in tapes. In the benzene complex the sheets contain only one kind of molecule or the other. The sheets containing the trichlorotricyanobenzene molecules have approximately linear C?N...Cl?C intermolecular interactions with N...Cl distances about 3.02 å.  相似文献   

5.
The structure of a liquid crystal of 4-cyano-4′-n-octyloxybiphenyl (C21H25NO) is determined by X-ray diffraction analysis. The compound crystallizes in the triclinic crystal system with unit cell parameters a = 7.322(1) Å, b = 12.693(3) Å, c = 20.393(2) Å, α = 92.45(1)°, β = 99.96(1)°, γ = 99.35(2)°, and space group $P\bar 1$ . The structure is solved by the direct method and refined to R = 0.057. Two independent molecules are located in the asymmetric unit. No short intermolecular contacts are observed in the crystal packing.  相似文献   

6.
The crystal structures of two host-guest molecular complexes of 18-crown-6 with 2-aminobenzoic acid hydrazide monohydrate (the ratio host: guest: H2O = 1: 2: 2) (complex I) and 5-amino-1-benzyl-1,2,3-triazole-4-carboxylic acid hydrazide (the host: guest ratio = 1: 2) (complex II) are determined by X-ray diffraction analysis. Crystals I are monoclinic, a = 8.468(2) Å, b = 17.378(3) Å, c = 10.517(2) Å, β = 96.88(3)°, space group P21/n, and R = 0.0393 for 6692 reflections. Crystals II are orthorhombic, a = 18.489(1) Å, b = 10.192(3) Å, c = 20.412(2) Å, space group Pbca, and R = 0.0540 for 3513 reflections. In both complexes, the centrosymmetric 18-crown-6 and guest molecules are joined together through the NH?O (crown) hydrogen bonds, which involve all the hydrogen atoms of the hydrazine group. The NH?O=C intramolecular hydrogen bond is observed in the guest molecule. In structure I, the water molecule serves as a bridge between the guest molecules related by the glide-reflection plane and combines the guest-host-guest complexes into layers. In structure II, the guest molecules are linked into chains through hydrogen bonds of the NH?O=C type; in turn, the chains composed of guest molecules and the crown ether molecules bonded to these chains form a layered structure.  相似文献   

7.
The para and ortho isomers of 3,5-dinitro-(4-acetylphenyl)aminobenzoyl (p-bromophenyl)amide (I and II, respectively) are synthesized, and their physicochemical properties and structure are investigated. The para isomer I has a higher melting temperature and is less soluble in organic solvents as compared to the ortho isomer II. The electronic absorption spectra indicate that absorption for molecule I occurs at longer wavelengths than for molecule II. A correlation between the physicochemical properties and the crystal structures of compounds I and II is revealed. Crystals I · 0.5C6H6 are triclinic; the unit cell parameters are a = 11.760(2) Å, b = 13.958(3) Å, c = 15.012(3) Å, α = 108.01(2)°, β = 103.95(1)°, γ = 92.00(2)°, V = 2258.3(8) Å3, space group $P\bar 1$ , and Z = 4. Crystals II are monoclinic; the unit cell parameters are a = 9.302(2) Å, b = 16.380(3) Å, c = 13.480(3) Å, β = 100.09(3)°, V = 2022.1(7) Å3, space group P21/c, and Z = 4. Structures I · 0.5C6H6 and II are characterized by intramolecular and intermolecular hydrogen bonds.  相似文献   

8.
The crystal and molecular structures of Ru3(CO)6{μ 3-OPPh2C2H(C6H4)PPhCH2PPh}-(μ 3-OPPh2)Ph (1) and Ru3(CO)6{μ-OPPh2C2H(C6H4)PPhO}(μ-PPh2)(μ-PPh2O) (2) have been determined by single crystal X-ray diffraction. Both complexes contain oxygen atoms oxidatively inserted into phosphorus–ruthenium bonds, and unique σ/π multidentate ligands formed from C $---{\text{H}}$ H and C $--$ P bond cleavage in bis(diphenylphosphino)acetylene and bis(diphenylphosphino)methane. Complex 1 crystallized in the triclinic space group ${\bar 1}$ , with lattice parameters a = 11.642(4) Å, b = 15.018(5) Å, c =16.587(5) Å, α = 2.48(3)°, β = 76.47(2)°, γ = 70.35(3)°, V = 2651.1(15) Å3, Z = 2. Complex 2 crystallized in the centered monoclinic space group, C2/c, with lattice parameters a = 34.467(4) Å, b = 14.274(2) Å, c = 23.258(3) Å, β = 5.29(1)°, V = 11394(3) Å3, Z = 8.  相似文献   

9.
The crystal structure of sanidine-like feldspar of the composition KAlSi3O8 from the Khibiny alkaline massif (the Kola Peninsula) has been refined (X-ray diffraction analysis; automated Syntex $P\bar 1$ diffractometer; 2θ: θ scanning technique; 2320 reflections; R (hkl) = 0.0409; anisotropic refinement; AREN program package). The data obtained for KAlSi3O8 are: a = 8.615(9), b = 13.030(7), c = 7.200(5) Å, α = 89.99(5)°, β = 116.01(6)°, γ = 89.98(7)°, Z = 4, sp. gr. $C\bar 1$ . Microtwinning revealed in the crystal structure of the mineral explains the simultaneous existence of two structural-optical types in one sample—“high” and “low” sanidines.  相似文献   

10.
The title compound 5-bromo-1-(2-cyano-pyridin-4-yl)-1H-indazole-3-carboxylic acid diethylamide, C18H16BrN5O, is prepared from 5-bromoindazole-3-carboxylic acid methylester. N 1-arylation is carried out with 4-chloro-2-cyanopyridine and the resulting product is converted to diethylamide by reacting with thionyl chloride and diethylamine. The structure is identified from its FT-IR, 1H NMR, 13C NMR spectroscopy, elemental analysis data and unambiguously confirmed by single crystal X-ray diffraction studies. There are two symmetry independent molecules in the asymmetric unit with no significant differences in bond lengths and angles. The title compound crystallizes in the triclinic system, space group \(P\bar 1\) , with a = 11.2330(2); b = 11.6130(2); c = 15.4710(3) Å, α = 92.515(1)°; β = 109.956(1)°; γ = 107.199(1)°; V = 1788.45(6)Å3 and z = 4. An intramolecular C-H…N hydrogen bond forms an S(6) ring motif in one of the unique molecules. In the crystal, two molecules are linked about a center of inversion by C-H…O hydrogen bonded dimers generating an R 2 2 (16) ring motif. The crystal packing is stabilized by C-H…N, C-H…O hydrogen bonds and π…π stacking interactions.  相似文献   

11.
The molecular and crystal structures of chiral 1R,4R-cis-2-(4-phenylbenzylidene)-n-menthan-3-one (I) have been determined by X-ray diffraction analysis. Crystals I are monoclinic, a = 6.755(3) Å, b = 9.860(3) Å, c = 14.103(6) Å, β = 98.95(1)°, space group P21, Z = 2, and R = 0.035 for 1031 reflections. A chair conformation of the cyclohexanone ring in the molecule is substantially distorted toward a “half-chair” conformation. The enone and benzylidene groupings are virtually planar (the torsion angles are equal to 13.0° and 4.9°, respectively). The benzene rings of the biphenyl fragment are rotated with respect to each other through an angle of 40°–43°. Among the compounds under consideration, the distortion of bond angles at the sp 2 carbon atoms of the benzylidene grouping as a criterion for the steric stress of molecules is maximum in structure I.  相似文献   

12.
Two cadmium halide complexes with 1,2-bis[2-(diphenylphosphinylmethyl)phenoxy]ethane (L 1) and 1,3-bis[2-(diphenylphosphinylmethyl)phenoxy]propane (L), namely, CdBr2 ? L 1 (I) and CdI2 ? L(II), have been synthesized. An analysis of their vibrational spectra is carried out. The structures of I and II are determined by X-ray diffraction. Crystals I are monoclinic, a = 31.562(6) Å, b = 13.548(3) Å, c = 18.733(4) Å, β = 91.28(3)°, space group C2/c, Z = 8, and R = 0.051 for 3776 reflections. Crystals II are triclinic, a = 11.803(2) Å, b = 12.554(3) Å, c = 14.686(3) Å, α = 90.30(3)°, β = 90.29(3)°, γ = 106.08(3)°, space group $P\bar 1$ , Z = 2, and R = 0.043 for 4916 reflections. Compounds I and II exhibit a polymeric chain structure. The potentially tetradentate ligands L 1 and L are coordinated to the metal atoms only through two phosphoryl oxygen atoms and fulfill the bidentate bridging function. The environment of the Cd atom is completed to the tetrahedral coordination by two Br atoms in complex I and two I atoms in complex II. The mean distances are as follows: Cd-Br, 2.526(2) Å; Cd-I, 2.695 Å; and Cd-O, 2.243(8) Å in I and 2.210(4) Å in II. The L 1 and L ligands in complexes I and II adopt an S-shaped conformation.  相似文献   

13.
Double potassium indium and rubidium indium phosphates K3In(PO4)2 (I) and Rb3In(PO4)2 (II) are synthesized by solid-phase sintering at T = 900°C. The compounds prepared are characterized by X-ray powder diffraction (I and II), X-ray single-crystal diffraction (II), and laser-radiation second harmonic generation. Structure I is solved using the Patterson function and refined by the Rietveld method. Both compounds crystallize in the monoclinic crystal system. For crystals I, the unit cell parameters are as follows: a = 15.6411(1) Å, b = 11.1909(1) Å, c = 9.6981(1) Å, β = 90.119(1)°, space group C2/c, R p = 4.02%, and R wp = 5.25%. For crystals II, the unit cell parameters are as follows: a = 9.965(2) Å, b = 11.612(2) Å, c = 15.902(3) Å, β = 90.30(3)°, space group P21/n, R 1 = 4.43%, and wR 2 = 10.76%. Structures I and II exhibit a similar topology of the networks which are built up of { In[PO4]2} (I) and { In2[PO4]4} (II) structural units.  相似文献   

14.
The crystal structures of two organosilicon compounds are studied by X-ray diffraction. Crystals of trans-2,8-dihydroxy-2,8-diphenyl-4,4′,6,6′,10,10′,12,12′-octamethylcyclohexasiloxane, C20H36O8Si6, (I) are triclinic; at 110 K, a = 11.476(1) Å, b = 12.106(1) Å, c = 13.636(1) Å, α = 94.337(1)°, β = 112.669(1)°, γ = 112.216(1)°, space group $P\bar 1$ , Z = 2, and R = 0.057 for 5069 reflections with F > 4σ(F). Crystals of trans-2,8-dihydroxy-2,4,4′,6,6′,8,10,10′,12,12′-decamethyl-5-carbahexacyclosiloxane, C11H34O7 Si6, (II) are tetragonal; at 293 K, a = b = 15.487(3) Å, c = 11.364(3) Å, space group P42/n, Z = 4, and R = 0.055 for 955 reflections with F > 4σ (F). It is found that the structure of compound I, in which the substituents at the Si(1) atom differ in volume and inductive effect, contains two crystallographically independent molecules with different conformations of the hexasiloxane ring. In structure II, the oxygen atom and the methylene group are statistically disordered as a result of the location of the molecule at the center of symmetry. Although the SiCSi angle [122.1(1)°] differs noticeably from the tetrahedral angle, its value is characteristic of cyclohexasiloxanes and is not related to the disorder.  相似文献   

15.
Compound (CN3H6)2[(UO2)2(C2O4)(CH3COO)4] is synthesized and characterized by IR spectroscopy and single-crystal X-ray diffraction [a = 8.5264(2) Å, b = 13.8438(4) Å, c = 10.7284(2) Å, β = 103.543(1)°, space group P21/n, Z = 2, and R = 0.0258]. The main structural units of the crystals are binuclear [(UO2)2C2O4(CH3COO)4]2? groups, which belong to the A 2 K 02 B 4 01 crystal chemical group of uranyl complexes (A = UO 2 2+ , K 02 = C2O 4 2? , and B 01 = CH3COO?). The coordination polyhedron of the uranium atom is the UO8 hexagonal bipyramid with the oxygen atoms of the uranyl ion at the axial positions. Uranium-containing groups and guanidinium cations are connected by electrostatic interactions and by the hydrogen bond system, which involves hydrogen atoms of guanidinium cations and oxygen atoms of oxalate and acetate anions. The results of the spectroscopic study of the compound agree with the X-ray diffraction data.  相似文献   

16.
The molecular and crystal structures of a complex of echinochrome (2,3,5,6,8-pentahydroxy-7-ethyl-1,4-naphthoquinone) with dioxane are determined. The molecular complex 2(C12H10O7) · C4H8O2 crystallizes in the form of dark red transparent thin plates. The crystal data of the compound are as follows: a = 4.563(1) Å, b = 6.382(1) Å, c = 22.812(4) Å, α = 91.955(5)°, β = 90.408(5)°, γ = 104.801(4)°, space group $P\overline 1 $ , and Z = 2. The crystal structure is solved by direct methods and refined to R 1 = 0.0656 and wR 2 = 0.1196.  相似文献   

17.
It is established that a one-layer polytype 1T with the unit-cell parameters a = 3.758, c = 12.135 Å, sp. gr. P3m1 and the structure module hThOhThE is mixed with the three-layer polytype 3R with the unit-cell parameters a = 3.758, c = 36.405 Å, sp. gr. R3m and the structure module hTcOcThE, where T and O are two-dimensional nets of tetrahedra and octahedra, respectively, E is the empty intermediate layer, and h and c indicate the hexagonal and cubic packings of atomic planes S. The microdiffraction pattern in the hexagonal basis shows a monoclinic superlattice with the parameters $A = \sqrt {19} a, B = \sqrt {13} a, \gamma = 110.485^\circ$ related to the main hexagonal lattice as A = [520] and $B = [\bar 130]$ .  相似文献   

18.
The crystal structure of [N-(2-carbamoylethyl)iminodiacetato]-aqua(1,10-phenanthroline) cobalt(III) chloride 3.5 hydrate [Co(Ceida)(H2O)(Phen)Cl · 3.5H2O (I) has been determined by 1H NMR technique and X-ray diffraction analysis. The crystals are triclinic, a = 10.352(2) Å, b = 12.534(3) Å, c = 20.665(4) Å, α = 107.02(3)°, β = 92.22(3)°, γ = 111.63(3)°, Z = 4, space group $P\bar 1$ , andR = 0.0438. The unit cell involves two crystallographically nonequivalent but virtually identical cationic complexes [Co(Ceida)(H2O)(Phen)]+. The tridentate chelate ligand Ceida 2? (N + 2O) occupies the face in the coordination octahedron of the Co atom, and the propionamide group remains free. The mean bond lengths are as follows: Co-OCeida, 1.876 Å; Co-NCeida, 1.981 Å; Co-NPhen, 1.945 Å; and Co-Ow, 1.915 Å. In the structure, the arrangement of cationic complexes and certain water molecules exhibits a pseudosymmetry (the 21 axis). The cations and water molecules are located in the layers, and the anions are arranged between the layers. The structural elements are linked by hydrogen bonds and van der Waals interactions.  相似文献   

19.
Single crystals of UO2(n-C3H7COO)2(H2O)2 (I) and Mg(H2O)6[UO2(n-C3H7COO)3]2 (II) are synthesized. Their IR-spectroscopic and X-ray diffraction studies are performed. Crystals I are monoclinic, a = 9.8124(7) Å, b = 19.2394(14) Å, c = 12.9251(11) Å, β = 122.423(1)°, space group P21/c, Z = 6, and R = 0.0268. Crystals II are cubic, a = 15.6935(6) Å, space group $Pa\bar 3$ , Z = 4, and R = 0.0173. The main structural units of I and II are [UO2(C3H7COO)2(H2O)2] molecules and [UO2(C3H7COO)3]? anionic complexes, respectively, which belong to AB 2 01 M 2 1 (I) and AB 3 01 (II) crystal chemical groups of uranyl complexes (A = UO 2 2+ , B 01 = C3H7COO?, and M 1 = H2O). A crystal chemical analysis of UO2 L 2 · nH2O compounds, where L is a carboxylate ion, is performed.  相似文献   

20.
Hydrazine 5-amino-1-benzyl-1,2,3-triazole-4-carboxylate hexafluorosilicate trihydrate (I) is synthesized. The crystal structure of the compound synthesized is determined. Crystals I are monoclinic, a = 13.353(1) Å, b = 21.094(2) Å, c = 20.233(2) Å, β = 94.05(3)°, space group P21/c, and R = 0.0584 for 16 601 reflections with I > 2σ(I). In the asymmetric part of the unit cell, four organic cations protonated at the terminal hydrazine nitrogen atoms, two hexafluorosilicate anions, and six water molecules are linked into a three-dimensional framework through hydrogen bonds of the N-H?F, N-H?O, and O-H?F types.  相似文献   

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