scholarly journals The structure of polyisoprenes. I. The crystal structure of geranylamine hydrochloride

1945 ◽  
Vol 183 (995) ◽  
pp. 388-404 ◽  
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Three Dimensional ◽  
Trans Configuration ◽  
Single Bond ◽  
Interatomic Distances ◽  
X Ray ◽  
Gutta Percha ◽  
Carbon Bonds ◽  
Molecular Dimensions

An X-ray analysis employing three-dimensional Fourier syntheses has established the crystal structure and molecular dimensions of the di-isoprene derivative, geranylamine hydrochloride. The molecules, which have a trans configuration and are therefore analogous to gutta- percha, lie parallel and end to end in pairs within an ionic framework where each nitrogen atom is equidistant from four chlorine neighbours. The two isoprene units are planar and have normal interatomic distances, but are linked by a C-C bond markedly shorter than a normal single bond. This unusual bond feature is accompanied by a coplanar arrangement with the adjacent carbon bonds.

The Structure of Polyisoprenes. I. The Crystal Structure of Geranylamine Hydrochloride

1946 ◽  
Vol 19 (2) ◽  
pp. 351-359
Author(s):  
G. A. Jeffrey
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Three Dimensional ◽  
Single Bond ◽  
Interatomic Distances ◽  
X Ray ◽  
Gutta Percha ◽  
Carbon Bonds ◽  
End To End ◽  
Molecular Dimensions

Abstract An x-ray analysis employing three-dimensional Fourier syntheses has established the crystal structure and molecular dimensions of the diisoprene derivative, geranylamine hydrochloride. The molecules, which have a transconfiguration and are therefore analogous to gutta-percha, lie parallel and end-to-end in pairs within an ionic framework, where each nitrogen atom is equidistant from four chlorine neighbors. The two isoprene units are planar and have normal interatomic distances, but are linked by a C—C bond markedly shorter than a normal single bond. This unusual bond feature is accompanied by a coplanar arrangement with the adjacent carbon bonds.

Crystal Structure of the Pyridinium Salt of the Polymeric Tris(thiocyanato)dicuprate(I) Anion

1979 ◽  
Vol 32 (12) ◽  
pp. 2757 ◽  
Author(s):  
CL Raston ◽  
B Walter ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Single Crystal ◽  
Title Compound ◽  
Three Dimensional ◽  
Pyridinium Salt ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dimensional Network

The title compound, [C5H6N]+ [Cu2(SCN)3]-, has been prepared and its crystal structure determined by single-crystal X-ray diffraction at 295(1) K. Crystals are monoclinic, Cc, a 11.238(7), b 11.644(4), c 10.020(4)Ǻ, β 102.67(3)°, Z 4, the structure being refined to a residual of 0.037 for the 960 'observed' reflections. The structure comprises a three-dimensional network of copper(I) atoms linked by bridging thiocyanate groups, the pyridinium counterions occupying sites in the network cavities. Both copper atoms are four-coordinate, one having an environment of one nitrogen atom [Cu-N, 1.926(9)Ǻ] and three sulfur atoms [Cu-S, 2.319(3), 2.421(3), 2.448(3)Ǻ], while the other is coordinated by two atoms of each type [Cu-N, 1.935(9), 1.947(10); Cu-S, 2.430(3), 2.493(4) Ǻ].

scholarly journals An investigation of polyhedral deformation in two mixed-metal diarsenates: SrZnAs2O7and BaCuAs2O7

2015 ◽  
Vol 71 (4) ◽  
pp. 330-337 ◽  
Author(s):  
Sabina Kovač ◽  
Ljiljana Karanović ◽  
Tamara Đorđević
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
General Formula ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
X Ray ◽  
Open Framework ◽  
Geometrical Characteristics ◽  
Barium Copper

Two isostructural diarsenates, SrZnAs2O7(strontium zinc diarsenate), (I), and BaCuAs2O7[barium copper(II) diarsenate], (II), have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction. The three-dimensional open-framework crystal structure consists of corner-sharingM2O5(M2 = Zn or Cu) square pyramids and diarsenate (As2O7) groups. Each As2O7group shares its five corners with five differentM2O5square pyramids. The resulting framework delimits two types of tunnels aligned parallel to the [010] and [100] directions where the large divalent nine-coordinatedM1 (M1 = Sr or Ba) cations are located. The geometrical characteristics of theM1O9,M2O5and As2O7groups of known isostructural diarsenates, adopting the general formulaM1IIM2IIAs2O7(M1II= Sr, Ba, Pb;M2II= Mg, Co, Cu, Zn) and crystallizing in the space groupP21/n, are presented and discussed.

The Crystal Structure of KIO3.HIO3

1971 ◽  
Vol 49 (3) ◽  
pp. 468-476 ◽  
Author(s):  
Lilian Y. Y. Chan ◽  
F. W. B. Einstein
Keyword(s):  
Crystal Structure ◽  
Three Dimensional ◽  
Monoclinic Space Group ◽  
X Ray ◽  
R Factor ◽  
Octahedral Environment ◽  
Distorted Octahedral ◽  
Potassium Hydrogen ◽  
A Cell ◽  
Least Squares Techniques

The crystal structure of potassium hydrogen di-iodate (bi-iodate) KIO3.HIO3 was determined from three dimensional X-ray data collected by counter methods. The structure was refined by full-matrix least-squares techniques to a conventional R factor of 5.0 % for the 1392 observed reflexions. The salt crystallizes in the monoclinic space group P21/c with eight formula units in a cell of dimension a = 7.028(1) Å, b = 8.203(1) Å, c = 21.841(3) Å, β = 98.03(1)°.The iodate units are all basically pyramidal; weak interionic I—O contacts complete a very distorted octahedral environment around three iodine atoms. There is a capped octahedral (7-coordinate) environment around the remaining iodine atom. The I—O bonds are in the range 1.75–1.82 Å and the I—OH bonds are 1.91 and 1.95 Å, variations in length can be correlated with differences in the degree of involvement in (a) hydrogen bonding and (b) interaction with adjacent iodine atoms.

The crystal structure of gatehouseite

2011 ◽  
Vol 75 (6) ◽  
pp. 2823-2832
Author(s):  
P. Elliott ◽  
A. Pring
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Three Dimensional ◽  
Direct Methods ◽  
Chemical Analyses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Manganese Phosphate ◽  
Phosphate Mineral ◽  
Unit Formula

AbstractThe crystal structure of the manganese phosphate mineral gatehouseite, ideally Mn52+(PO4)2(OH)4, space group P212121, a = 17.9733(18), b = 5.6916(11), c = 9.130(4) Å, V= 933.9(4) Å3, Z = 4, has been solved by direct methods and refined from single-crystal X-ray diffraction data (T = 293 K) to an R index of 3.76%. Gatehouseite is isostructural with arsenoclasite and with synthetic Mn52+(PO4)2(OH)4. The structure contains five octahedrally coordinated Mn sites, occupied by Mn plus very minor Mg with observed <Mn—O> distances from 2.163 to 2.239 Å. Two tetrahedrally coordinated P sites, occupied by P, Si and As, have <P—O> distances of 1.559 and 1.558 Å. The structure comprises two types of building unit. A strip of edge-sharing Mn(O,OH)6 octahedra, alternately one and two octahedra wide, extends along [010]. Chains of edge- and corner-shared Mn(O,OH)6 octahedra coupled by PO4 tetrahedra extend along [010]. By sharing octahedron and tetrahedron corners, these two units form a dense three-dimensional framework, which is further strengthened by weak hydrogen bonding. Chemical analyses by electron microprobe gave a unit formula of (Mn4.99Mg0.02)Σ5.01(P1.76Si0.07(As0.07)Σ2.03O8(OH)3.97.

Synthesis, crystal structure and molecular conformation of (±)-1-oxoferruginol and (±)-shonanol

2004 ◽  
Vol 219 (10) ◽  
Author(s):  
Swastik Mondal ◽  
Monika Mukherjee ◽  
Arnab Roy ◽  
Debabrata Mukherjee
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Diffraction Data ◽  
Molecular Conformation ◽  
Membered Ring ◽  
Methyl Groups ◽  
Single Bond ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Structures

Abstract(±)-1-oxoferruginol and (±)-shonanol, two potential intermediates in the synthesis of tricyclic diterpenoid ferruginol, have been prepared and crystal structures of the compounds have been investigated using single-crystal X-ray diffraction data. The methyl groups of the isopropyl moiety in (±)-shonanol are disordered over two positions with occupation factors 0.65(1) and 0.35(1), respectively. Although the chemical structures of two compounds are very similar, a C—C single bond in the terminal six-membered ring of (±)-1-oxoferruginol is replaced by a C=C bond in (±)-shonanol, the quantitative isostructurality index calculations indicate that the structures are not isostructural. Intermolecular O—H…O hydrogen bonds between pairs of molecules in the compounds related by center of inversion lead to characteristic dimers forming R

scholarly journals X-Ray Single Crystal Structural Analysis of Magnetically Oriented Microcrystals

2014 ◽  
Vol 70 (a1) ◽  
pp. C1138-C1138
Author(s):  
Chiaki Tsuboi ◽  
Kazuki Aburaya ◽  
Shingo Higuchi ◽  
Fumiko Kimura ◽  
Masataka Maeyama ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Single Crystal ◽  
Three Dimensional ◽  
Diffraction Measurement ◽  
X Ray Diffraction ◽  
Data Set ◽  
Uv Curable ◽  
X Ray

We have developed magnetically oriented microcrystal array (MOMA) technique that enables single crystal X-ray diffraction analyses from microcrystalline powder. In this method, microcrystals suspended in a UV-curable monomer matrix are there-dimensionally aligned by special rotating magnetic field, followed by consolidation of the matrix by photopolymerization. From thus achieved MOMAs, we have been succeeded in crystal structure analysis for some substances [1, 2]. Though MOMA method is an effective technique, it has some problems as follows: in a MOMA, the alignment is deteriorated during the consolidation process. In addition, the sample microcrystals cannot be recovered from a MOMA. To overcome these problems, we performed an in-situ X-ray diffraction measurement using a three-dimensional magnetically oriented microcrystal suspension (3D MOMS) of L-alanine. An experimental setting of the in-situ X-ray measurement of MOMS is schematically shown in the figure. L-alanine microcrystal suspension was poured into a glass capillary and placed on the rotating unit equipped with a pair of neodymium magnets. Rotating X-ray chopper with 10°-slits was placed between the collimator and the suspension. By using this chopper, it was possible to expose the X-ray only when the rotating MOMS makes a specific direction with respect to the impinging X-ray. This has the same effect as the omega oscillation in conventional single crystal measurement. A total of 22 XRD images of 10° increments from 0° to 220° were obtained. The data set was processed by using conventional software to obtain three-dimensional molecular structure of L-alanine. The structure is in good agreement with that reported for the single crystal. R1 and wR2 were 6.53 and 17.4 %, respectively. RMSD value between the determined molecular structure and the reported one was 0.0045 Å. From this result, we conclude that this method can be effective and practical to be used widely for crystal structure analyses.

Synthese und Kristallstruktur des Dichloroselenonitren-Komplexes (PPh4)2[WCl5(NSeCl2)] / Synthesis and Crystal Structure of the Dichloro-selenonitrene Complex (PPh4)2[WCl5(NSeCl2)]

1992 ◽  
Vol 47 (3) ◽  
pp. 301-304 ◽  
Author(s):  
Stefan Vogler ◽  
Kurt Dehnicke
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Structure Determination ◽  
Selenium Atom ◽  
Tungsten Atom ◽  
Chlorine Atoms ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
Trigonal Bipyramidal ◽  
Distorted Octahedral

The title compound has been prepared by the reaction o f [WCl4(NSeCl)]2 with PPh4Cl in CH2Cl2 solution. It forms red crystals, which were characterized by an X-ray structure determination. Space group P21/c, Z = 4, 3856 observed unique reflections, R = 0.073. Lattice dimensions at 25 °C: a = 2266.0(5), b = 1121.0(2), c = 2013.0(4) pm, β = 109.66(3)°. The structure consists o f PPh4+ ions and anions [WCl5(NSeCl2)]2-, in which the tungsten atom is surrounded in a distorted octahedral way by five chlorine atoms and by the nitrogen atom of the (NSeCl2)3- ligand. The W = N = SeCl2 group is characterized by WN and SeN double bonds; the selenium atom has a pseudo trigonal-bipyramidal coordination with the N atom and two lone pairs in equatorial and the chlorine atoms in axial positions.

scholarly journals An Unexpected Trinuclear Cobalt(II) Complex Based on a Half-Salamo-Like Ligand: Synthesis, Crystal Structure, Hirshfeld Surface Analysis, Antimicrobial and Fluorescent Properties

Crystals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 408 ◽  
Author(s):  
Ruo-Yan Li ◽  
Xiao-Xin An ◽  
Juan-Li Wu ◽  
You-Peng Zhang ◽  
Wen-Kui Dong
Keyword(s):  
Crystal Structure ◽  
Surface Analysis ◽  
Three Dimensional ◽  
Antimicrobial Activities ◽  
Hirshfeld Surface ◽  
Hirshfeld Surface Analysis ◽  
Fluorescent Properties ◽  
X Ray ◽  
X Ray Crystallography ◽  
Elemental Analyses

An unexpected trinuclear Co(II) complex, [Co3(L2)2(μ-OAc)2(CH3OH)2]·2CH3OH (H2L2 = 4,4′-dibromo-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol) constructed from a half-Salamo-based ligand (HL1 = 2-[O-(1-ethyloxyamide)]oxime-4-bromophenol) and Co(OAc)2·4H2O, has been synthesized and characterized by elemental analyses, infrared spectra (IR), UV-Vis spectra, X-ray crystallography and Hirshfeld surface analysis. The Co(II) complex contains three Co(II) atoms, two completely deprotonated (L2)2− units, two bridged acetate molecules, two coordinated methanol molecules and two crystalline methanol molecules, and finally, a three-dimensional supramolecular structure with infinite extension was formed. Interestingly, during the formation of the Co(II) complex, the ligand changed from half-Salamo-like to a symmetrical single Salamo-like ligand due to the bonding interactions of the molecules. In addition, the antimicrobial activities of HL1 and its Co(II) complex were also investigated.

The Structure of Polyisoprenes. II. The Structure of β-Gutta-Percha

1945 ◽  
Vol 18 (2) ◽  
pp. 280-283
Author(s):  
G. A. Jeffrey
Keyword(s):  
Molecular Structure ◽  
Double Bond ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Interatomic Distances ◽  
Methyl Group ◽  
X Ray ◽  
Gutta Percha ◽  
Qualitative Estimate

Abstract The x-ray diffraction data at present available from β-gutta-percha are shown to be insufficient to distinguish fine details of molecular structure. Since a qualitative estimate of the intensities on the fibre diagram can be adequately satisfied by a model having normal interatomic distances and valency angles, no evidence exists for the improbable distortion of the methyl group out of the plane of the double bond previously ascribed to the molecule.

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