An X-ray diffraction refinement of the crystal structure of natural apophyllite

The crystal structure of apophyllite (Andersberg — GDR), with a = 8.966(2), c = = 15.767(1) Å, P4/mnc, z = 2, Q = 2.35 gm · cm⁻³, has been refined (R = 0.035) by least squares with 976 reflections collected with a diffractometer. Apophyllite is a sheet structure with the bringing Si O bond lengths 1.6236 Å, while the non-bridging bond length Si O(3) is 1.5843 Å. The two independent Si O Si angles are 140.09, 140.76 degrees. The mean Si O bond length is 1.6138 Å. As it was not possible to locate unequivocally the H-atoms with the X-ray data, the interpretation of the of water in the structure was based on the charge balance approach of DONNAY and ALLMAN . Assuming that the fluorine ion is bonded to calcium ion (Ca-F = = 2.416 Å) and to H3 atom (F-H3 = 0.9145(1) Å) and water molecule hydrogen bonded to silicate framework. The average bond distances O-H are 0.962(2) Å and angle 105.24(1)°.     

The molecular and crystal structure of 2-oxo-1-pyrrolidine-acetamide

C₆H₁₀N₂O₂, P1 , a = 6,607(2) Å, b = 8,538(2) Å, c = 6,392(2) Å, α = 102,43(2)°, β = 91,11(2)°, y = 79,82(2)°, V = 349,1 ų, Z = 2, D_m = 1,36 g × cm⁻³, D_x = 1,35 g × × cm⁻³, MoKα radiation, λ = 1.71069 Å, μ(MoKα) = 1.11 cm⁻¹. The structure was solved by direct methods. The parameters were refined by full matrix least squares technique to a final R = 0.088 for 834 reflections with ∥F₀∥ > 4σ(F₀). The dihedral angle between the least-squares plane through the pyrrolidine ring and that through the acetamide group is 90.4°. The N H … O hydrogen bonds connect molecules to form bands parallel to the z axis.     

Crystal structures of four inclusion compounds of 2,2′-dithiosalicylic acid and tetraalkylammonium

Herein four inclusion compounds of 2,2′-dithiosalicylic acid and tetraalkylammonium, 2(CH₃)₄N⁺·C₁₄H₈O₄S₂^2?·H₂O (1), (C₂H₅)₄N⁺·C₁₄H₉O₄S₂^?·0.25H₂O(2), (n-C₃H₇)₄N⁺·C₁₄H₉O₄S₂^? (3) and (n-C₄H₉)₄N⁺·C₁₄H₉O₄S₂^?(4) are prepared and characterized by X-ray single crystal diffraction. As shown in the results, compounds 1 and 3 belong to orthorhombic crystal system with different space groups of P2₁2₁2₁ and Pca2₁, and 2 and 4 are monoclinic system with similar groups of P2₁/n and P2₁/c. The crystallography data are displayed below: 1: a = 10.5903(7) Å, b = 10.6651(7) Å, c = 21.9476(13) Å, V = 2478.9(3) ų, Z = 4, R₁ = 0.0359; 2: a = 8.13340(1) Å, b = 22.0741(3)Å, c = 13.2143(2)Å, β = 101.6360(1) °, V = 2323.70(6) ų, Z = 1, R₁ = 0.0385; 3: a = 15.7857(2) Å, b = 8.24830(1) Å, c = 20.2599(2) Å, V = 2637.94(5) ų, Z = 4, R₁ = 0.0308_degree4: a = 11.7476(2) Å, b = 17.1346(1) Å, c = 16.3583(3)Å, β = 109.4560(1) °, V = 3104.74(9)ų, Z = 4, R₁ = 0.0562. Interestingly, although the carbon chains of the guest templates vary from methyl group to butyl group, the host molecules of 2,2′-dithiosalicylic acid all construct the similar 2D hydrogen-bonded host layers with or without the existence of water molecules to contain the guest templates to yield analogous sandwich-like inclusion compounds. Obviously, although the guest templates will have certain effects on the ultimate formation of these crystal structures, the host molecule of 2,2′-dithiosalicylic acid is a controlling factor to form these four inclusion compounds.     

Crystal Structure Investigation of 2-Pheny limidazo [f]1,10-phenanthroline

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 ų, D_cal = 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 R_w = 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.     

Powder study of propanthioamide dervative C8H6N2S2

The crystal structure of 2‐cyano‐3‐(2‐thienyl)prop‐2‐enethioamide (C₈H₆N₂S₂), a propanethioamide derivative was solved from high resolution laboratory X‐ray powder diffraction data collected at ambient conditions. Structure determination was performed by means of the global optimization method of simulated annealing at a resolution of 1.5 Å. Rietveld refinement yielded an R_WP value of 4.02% (P2₁/a, a = 15.8174(2) Å, b = 5.6502(1) Å, c = 11.0952(1) Å, β = 116.9923(7)°, V = 883.6(5) ų, Z = 4). The molecules are stacked in parallel layers and are stabilized by hydrogen bonds. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal structure,thermal analysis and IR spectrometric investigation of bis (2‐amino‐6‐methyl) pyridinium sulfate

The synthesis method, crystal structure determination, phase transitions studied by thermal analysis and IR spectrometric investigation of 2C₆H₉N₂⁺.SO₄^2– are reported. The compound crystallizes in the monoclinic space group C2/c (no. 15) with a = 10.5068(4) Å, b = 10.2225(5) Å, c = 14.0422(7) Å, and β = 104.489(3)°. The atomic arrangement can be described by layers built by all the components of the structure and centered by planes z = 1/4 and 3/4. The organic molecules form channels parallel to the c direction with dimensions of 4.163(1)Å and 5.148(4)Å. Thermal analysis shows that the anhydrous compound presents an irreversible weak phase transition. The IR study, based on theoretical analyses and on the literature data allows the interpretation of the IR spectrum. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The Crystal and Molecular Structure of 4'-Cyanophenyl-4-n-Pentylbenzoate

The crystal and molecular structure of the title compound with the formula C₅H¹¹—C₆H₄—COO—C₆H₄—CN (CPPB) has been determined by X-ray diffraction methods. CPPB crystallizes in the monoclinic space group P2₁/n with eight molecules in a unit cell of dimensions a = 15.268(2) Å, b = 9.165(1) Å, c = 24.031(3) Å, β = 94.67(1)°. The structure has been solved by direct methods and refined to an R value of 0.070.

The CPPB molecules adopt a stretched form and are packed in an approximate parallel imbricated mode, the molecular long axes making an angle of about 5° with the crystal c axis. The molecular geometry and packing are discussed in relation to the mesomorphic behavior of CPPB.     

The crystal structure of nematogenic 2-bromo-1,4-phenylenediyl bis(trans-4-n-propylcyclohexanoate) — a special kind of disorder

The title compound with the formula C₃H₇–C₆H₁₀–COO–C₆H₃Br OOC C₆H₁₀ C₃H₇ (BPBPC) crystallizes in a triclinic unit cell with dimensions a = 5.822(2), b = 8.732(3), c = 13.016(5) Å, α = 94.42(3)°, β = 93.47(3)°, γ = 104.85(2)° containing one molecule. The structure has been solved by heavy atom method and refined to R = 0.083. The BPBPC molecules adopt an optimum stretched form and exhibit pseudo-centrosymmetry in consequence of a special kind of disorder within the crystal lattice.     

Structure and conformation of n‐ (t‐butoxycarbonyl)‐l‐valine‐l‐phenylalanine‐methyl ester (Boc‐Val‐Phe‐OMe)

The crystal structure of N‐ (t‐butoxycarbonyl) ‐ L‐valine‐L‐phenylalanine‐methyl ester (Boc‐Val‐Phe‐OMe), C₂₀H₃₀N₂O₅ was determined by X‐ray diffraction methods. The dipeptide crystallizes in orthorhombic space group P2₁2₁2₁, with cell parameters a = 5.0680(1) Å, b = 13.8650(1) Å and c = 28.2630(1) Å, V = 2143.8(5) ų, F.W. = 378.46, Z = 4, D_calc = 1.173 Mg/m³, μ = 0.687 mm^‐1, F₀₀₀ = 816, CuKα = 1.5418 Å. The structure was solved by direct methods and final R1 and wR2 are 0.0659 and 0.1654, respectively. The peptide unit is in trans conformation [ω = 177.4(9)°]. The conformation angles ϕ₁, ψ₁, ϕ₂ and ψ₂ for the peptide backbone are: ‐96.5(13)°, 101.2(13)°, ‐123.9(12)° and 34.0(15)°. The N‐H…O and C‐H…O hydrogen bondings influence the packing of the molecules in the dipeptide crystal. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Die Molekül- und Kristallstruktur des N-Methyl-piperidinium-acet-para-brom-anilid-jodid

N-Methyl-piperidinium-acet-para-bromo-anilide-iodide crystallizes in the triclinic space group P 1 with two formula units C₁₄H₂₀N₂OBrJ and two H₂O molecules in the unit cell. The lattice constants are a = 8.950 Å, b = 14.721 Å, c = 7.440 Å, α = 80.19°, β = 112.57° and γ = 106.82°. The molecular structure of the compound was determined by the X-ray structure analysis and the interaction between the molecules in the crystal was investigated. Especially the influence of the water in the crystal on the form of the molecule was analysed.     

The crystal and molecular structure of three homologue 1,4-dialkanoyloxy-biphenyls (SYM-n)

The three homologue compounds with the general formula C_nH_2n+1 COO C₆H₄ C₆H₄ OOC C_nH_2n+1 (SYM-n) crystallize in the following space groups: SYM-1: triclinic, P1 , a = 7.400(6), b = 9.227(3), c = 10.579(3) Å, α = 85.97(3), β = 89.09(3), γ = 71.47(3)°; SYM-2; monoclinic, P2₁/c, a = 11.712(7), b = 5.648(1), c = 12.408(6), Å, β = 103.84(3)°; SYM-5: triclinic, P1, a = 5.505(4), b = 8.342(8), c = 24.79(2) Å, α = 86.67(3), β = 85.45(6), γ = 71.74(7)°. The structures have been solved by direct methods and refined to R = 0.075, 0.061 and 0.053, respectively. The packing arrangements show a layer-like structure. The layers are almost separated for SYM-1 as well as for SYM-2 and interdigitated for the structure of SYM-5.     

Crystal and Molecular Structure of Non-hydrated and Hydrated Piperidinium-acet-o-Cl-anilide-chloride

Crystallizations from water and alcoholic solution respectively yield different crystal and molecular structures of Piperidinium-acet-o-Cl-anilide-chloride. The non-hydrated compound crystallizes from alcoholic solution in the space group P 2₁/c with 4 formula units C₁₃H₁₈N₂OCl₂ in the unit cell of dimensions a = 12.352 Å, b = 6.864 Å, c = 19.018 Å and β = 113.98°. The hydrated modification has the space group C 2/c with 8 formula units C₁₃H₁₈N₂OCl₂ and 8 H₂O molecules in the unit cell. The lattice constants are a = = 24.159 Å, b = 8.966 Å, c = 14.179 Å and β = 90.50°. The X-ray structure analyses were carried out to investigate the hydrogen bonds and the change of the molecular conformation caused by linking of water molecules to the drug molecules.     

Crystal structure determination of bis-dimethyl heptamethine cyanine chloride,C11N2H19Cl · 4 H2O

Mr = 286.59, monoclinic superposition structure C 121, Z = 4, a = 15.248(3), b = = 6.942 (3), c = 9.074(1) Å, β = 120.1(1)°, V = 827(1) ų, D_m = 1.13(1) Mg m⁻³, D_x = = 1.15 Mg m⁻³, λ(MoK_α) = 0.71069 Å, μ = 0.243 mm⁻¹, F (000) = 312, T = 296 K, final R = 0.061 for 802 reflections. All hydrogen atoms were located. The structure consists of chloride anions, bis-dimethyl heptamethine cyanine cations and water molecules. The structure of bis-dimethyl heptamethine cyanine chloride is disordered, e.g. there exist partial coincidence operations, leading to more than one stacking mode of the bis-dimethyl heptamethin cyanine chains. The crystal structure consists of rows of molecule along the a-axis. The C C bonds show the bond length compensation, typical of polymethines, towards a partial double bond (mean value 1.38 Å) between formally sp²-hybridized C atoms. The C N bond lengths to the methyl carbon atoms (mean value 1.49 Å) correspond to normal C N single bonds. The valence angles at the C atoms of the heptamethine chain clearly alternate and deviate systematically from 120°. This is also observed in other structures of a similar type. The structure determined by X-ray analysis confirms the chemical results.     

The Crystal and Molecular Structure of 1-Allyl-5-benzoyl-4-phenylpyrimidine-2-one hemihydrate

The crystal structure of C₂₀H₁₆N₂O₂. 0.5 H₂O has been determined from three dimensional X-ray diffraction data. The crystals are monoclinic, space group C 2/c, with a = 24.491(3) Å, b =10.241(2) Å, c = 16.643(2) Å, β =126.63(1)°, V = 3350.0(9) ų, D_calc = 1.290 g. cm⁻³, Z = 8. The structure was solved by direct methods and refined by least-squares methods to a final R = 0.0625 for 1358 observed unique reflections (F² ⩾ 2σ(F²)].     

Crystal and molecular structure of 5-diazo-2,2-dimethyl-4,6-dioxo-1,3-dioxane and 5-diazo-1,3-dimethylpyrimidin-2,4,6-trione

C₆N₂O₄H₆: M_r = 170.12, orthorhombic space group Pbca, a = 6.751(2), b = 13.669(4), c = = 16.845(4) Å, V = 1555(1) ų, D_x = 1.248 Mgm⁻³, Z = 8, F(000) = 704, λ(moKα) = 0.71069 Å, μ = 1.1 mm⁻¹. The crystal structure was determined by direct methods and refined by least-squares procedure to the discrepancy factor R = 0.039. C₆N₄O₃H₆: M_r = 182.14, monoclinic space group C2/c, a = 17.726(8), b = 6.191(12), c = 16.062(6) Å, β = 117.59 (3)°, V = 1562 (1) ų, D_x = 1.549 Mgm⁻³, Z = 8, F(000) = 752, λ(MoKα) = 0.71069 Å, μ = 1.2 mm⁻¹. The crystal structure was determined by direct methods and refined by least-squares procedure to the discrepancy factor R = 0.056.     

Crystal structure investigation of [Mn(3-CH3C5H4N)2(N3)2(H2O)2]

The crystal structure of the title compound has been determined by single crystal X-ray diffraction methods. [Mn(3-CH₃C₅H₄N)₂(N₃)₂(H₂O)₂] crystallizes in the space group P 1 with a = 7.444(2) Å, b = 7.691(2) Å, c = 8.926(3) Å, α = 99.82(3)°, β = 108.80(2)°, γ = 114.99(2)° and Z = 1. Least squares refinement gave a R value of R_w = 0.046 for 1414 observed reflections. The manganese atom in the title complex is octahedrally coordinated by two oxygen atoms of the water molecules and four nitrogen atoms; two N-atoms are the end atoms of azide groups and the other two nitrogen atoms belong to the 3-methylpyridine molecules. The polyhedra are linked via hydrogen bonds between the water molecules and the azide groups.     

Crystal structure of 2‐(2'‐hydroxyphenyl)‐6‐tributylstannyl‐4‐(3H )‐quinazolinone and 2‐(2'‐hydroxyphenyl)‐6‐iodo‐4‐(3H)‐quinazolinone

The structures of the title compounds C₂₆H₃₇N₂O₂Sn ( I ) and C₁₄H₉IN₂O₂ ( II ) were determined by single‐crystal X‐ray diffraction technique. Compound I crystallizes in the triclinic space group P1 with a = 9.560(3) Å, b = 16.899(6) Å, c = 17.872(5) Å, α = 65.957(7)°, β = 83.603(5)°, γ ( = 75.242(5)°, V = 2549.8(13) ų, Z = 4, and D =1.374 g/cm³. The compound consists of a quinazolinone ring with phenol and tributylstannyl moieties. Compound II crystallizes in the monoclinic space group P2₁/c with a = 7.6454(12) Å, b = 5.9270(9) Å, c = 27.975(4) Å; α = 90°, β = 95.081(3)°, γ = 90°, V = 1262.7(3) ų, Z = 4, and D = 1.915 g/cm³. The compound consists of a quinazolinone ring with phenol and iodine substituents. For both I and II , the short intramolecular O–H…N and two long intermolecular N–H…O hydrogen bonds are highly effective in holding the molecular system in a stable state. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal and Molecular Structure of mer-Co(4-CH3C5H4N)3(N3)3

The crystal structure of mer-Co(4-CH₃C₅H₄N)₃(N₃)₃has been determined by single crystal X-ray methods at 300 K. The compound crystallizes in the monoclinic space group C 2/c, a = 19.087(6), b = 16.769(4), c = 15.845(4) Å, β = 119.04(2)°, V = 4434(2) ų, M_r = 464.42. Z = 8, D_x = 1.391 Mgm⁻³, F(000) = 1920, λ (MoKα) = 0.71069 Å, μ = 0.802 mm⁻¹. The cobalt(III) ions are octahedrally coordinated to three azide groups and to three 4-methyl-pyridine molecules to form isolated coordination polyhedra.     

The Preparation and Crystal Structure of MgP4

In the systematical study of the A¹¹B^V semiconducting compounds the Mg-P system has been examined. Among the products of crystallization from Bi Pb Sn alloy the crystals of a new compound MgP₄ have been identified. It has been found that these crystals are isostructural with CdP₄. The crystal structure refinement from X-ray data has been performed. The lattice constants are: a = 5.141 Å, b = 5.079 Å, c = 7.518 Å, β = 98.64°; Z = 2; space group P2₁/c.     

The crystal and molecular structure of the Nematogenic Compound 5,8-Dihydro-5,8-methano-1,4-naphthalenediyl Bis(4-ethoxybenzoate)

Single crystals of the title compound with the formula (C₂H₅O C₆H₄ COO)₂C₁₁H₈ have been investigated by X-ray analysis. The compound crystallizes in the monoclinic space group P2₁/n with a = 8.555(1), b = 15.280(2), c = 19.093(3) Å, β = 94.17(1)⁰, V = 2489.2(5) ų, and Z = 4. The structure was solved by direct methods and refined to a final R value of 0.062 The molecule adopts an almost stretched form. The norbornene skeleton within the central part of the molecule is disordered and occurs in two different conformations. The molecular packing is characterized by different lattice regions: the molecules in one region are parallel but their long axes are inclined by 49.5° to the molecules of the other region.