scholarly journals The crystal structure of sucrose sodium bromide dihydrate

1947 ◽  
Vol 190 (1021) ◽  
pp. 257-272 ◽  
Keyword(s):  
Crystal Structure ◽  
Direct Proof ◽  
The Other ◽  
Sodium Bromide ◽  
Water Molecules ◽  
Hydroxyl Groups ◽  
Pyranose Ring ◽  
Complete Structure ◽  
The Mean ◽  
First Time

The complete crystal structure of sucrose sodium bromide dihydrate has been determined. The crystals are orthorhombic, with space-group P 2 1 2 1 2 1 , and cell-edges a =21.92, b =9.72, c =8.43 A. The bromine positions were obtained from Patterson-Harker syntheses, and the signs of the F ’s of the (0 kl ), ( h 0 l ) and ( hk 0) planes from the change of intensity from the chloride to bromide compounds. Fourier projections parallel to the three axes were used to determine the complete structure. In the structure the pyranose ring of the molecule is of the Sachse trans form. The furanose ring is an unexpectedly compact grouping, and one member of the ring is displaced from the plane of the other four. The configuration of both rings is such as to allow the groups attached to the ring atoms to approach as nearly as possible to the mean plane of each ring. Direct proof that sucrose may be described as α - d -glucopyranosido- β - d -fructofuranoside has been obtained for the first time. The sucrose molecules are held together by bonds from the hydroxyl groups to the Na and Br ions and to the water molecules, the hydroxyl groups each having two external bonds. The method used of reducing the observed intensities to an absolute scale is described, and the proof of the correctness of the structure is given as a set of diagrams of calculated and observed electron density.

scholarly journals Crystal structures of two nickel(II) macrocyclic salts: (5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)nickel(II) bis(perchlorate) monohydrate and (5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)nickel(II) dibromide trihydrate

2019 ◽  
Vol 75 (3) ◽  
pp. 332-337
Author(s):  
Peter W. R. Corfield ◽  
Virgil L. Goedken
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
The Other ◽  
Water Molecules ◽  
Asymmetric Unit ◽  
The Mean ◽  
The Many ◽  
Hydrogen Bonded

The crystal structure of the Ni-14 macrocycle salt, (5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)nickel(II) bis(perchlorate) hemihydrate, [Ni(C16H36N4)]2(ClO4)4·H2O, contains two different diasteriomeric macrocyclic cations in the asymmetric unit, one with two NH protons on each side of the cation (Ia), and the other with all four NH protons on the same side (Ib). The crystal structure of the bromide trihydrate salt of the same Ni-14 macrocyclic cation, namely (5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)nickel(II) dibromide trihydrate, [Ni(C16H36N4)]Br2·3H2O (II), contains only the same diastereomer as Ib, with the four N—H bonds on the same side. The geometry around the Ni atom differs slightly between the two diastereomeric cations, as the mean Ni—N distance in Ia is 1.952 (2) Å, while that for Ib and II is 1.928 (2) Å. The hexamethyl substitution in all three macrocyclic cations has the two dimethyl-substituted C atoms cis to one another, different from the trans 5,5,7,12,12,14-hexamethyl Ni-14 cations found in all but one of the many published crystal structures of hexamethyl Ni-14 macrocycles. In each of the two crystal structures, the anions, water molecules, and N—H protons of the macrocyclic cations form extensive hydrogen-bonded zigzag chains propagating along [001] in I and [010] in II.

Structural Studies on N-(2,4,6-Trimethylphenyl)-methyl/ chloro-acetamides, 2,4,6-(CH3)3C6H2NH-CO-CH3–yXy (X = CH3 or Cl and y = 0, 1, 2)

2006 ◽  
Vol 61 (10-11) ◽  
pp. 588-594 ◽  
Author(s):  
Basavalinganadoddy Thimme Gowda ◽  
Jozef Kožíšek ◽  
Hartmut Fuess
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structural Data ◽  
The Other ◽  
Side Chain ◽  
Structural Studies ◽  
Asymmetric Unit ◽  
Lattice Constants ◽  
Peptide Linkage ◽  
The Mean

TMPAThe effect of substitutions in the ring and in the side chain on the crystal structure of N- (2,4,6-trimethylphenyl)-methyl/chloro-acetamides of the configuration 2,4,6-(CH3)3C6H2NH-COCH3− yXy (X = CH3 or Cl and y = 0,1, 2) has been studied by determining the crystal structures of N-(2,4,6-trimethylphenyl)-acetamide, 2,4,6-(CH3)3C6H2NH-CO-CH3 (); N-(2,4,6- trimethylphenyl)-2-methylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2-CH3 (TMPMA); N-(2,4,6- trimethylphenyl)-2,2-dimethylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH(CH3)2 (TMPDMA) and N-(2,4,6-trimethylphenyl)-2,2-dichloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CHCl2 (TMPDCA). The crystallographic system, space group, formula units and lattice constants in Å are: TMPA: monoclinic, Pn, Z = 2, a = 8.142(3), b = 8.469(3), c = 8.223(3), β = 113.61(2)◦; TMPMA: monoclinic, P21/n, Z = 8, a = 9.103(1), b = 15.812(2), c = 16.4787(19), α = 89.974(10)◦, β = 96.951(10)◦, γ =89.967(10)◦; TMPDMA: monoclinic, P21/c, Z = 4, a =4.757(1), b= 24.644(4), c =10.785(2), β = 99.647(17)◦; TMPDCA: triclinic, P¯1, Z = 2, a = 4.652(1), b = 11.006(1), c = 12.369(1), α = 82.521(7)◦, β = 83.09(1)◦, γ = 79.84(1)◦. The results are analyzed along with the structural data of N-phenylacetamide, C6H5NH-CO-CH3; N-(2,4,6-trimethylphenyl)-2-chloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)-acetamide, 2,4,6-Cl3C6H2NH-COCH3; N-(2,4,6-trichlorophenyl)-2-chloroacetamide, 2,4,6-Cl3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)- 2,2-dichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CHCl2 and N-(2,4,6-trichlorophenyl)- 2,2,2-trichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CCl3. TMPA, TMPMA and TMPDCA have one molecule each in their asymmetric units, while TMPDMA has two molecules in its asymmetric unit. Changes in the mean ring distances are smaller on substitution as the effect has to be transmitted through the peptide linkage. The comparison of the other bond parameters reveal that there are significant changes in them on substitution.

Crystal Structure of Calcium Picrate Pentahydrate: A New Eight-Coordinate Stereochemistry for [M(bidentate)2(unidentate)4]

1979 ◽  
Vol 32 (2) ◽  
pp. 301 ◽  
Author(s):  
V Diakiw ◽  
TW Hambley ◽  
DL Kepert ◽  
CL Raston ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Water Molecule ◽  
Single Crystal ◽  
Title Compound ◽  
Lattice Site ◽  
The Other ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Triangular Face ◽  
X Ray

The crystal structure of the title compound, Ca(C6H2N307)2,5H2O, has been determined by single-crystal X-ray diffraction at 295(1) K and refined by least squares to a residual of 0.049 for 1513 'observed' reflections. Crystals are orthorhombic, Pmab, a 24.169(6), b l0.292(7), c 8.554(2) �, Z 4. The stereochemistry about the calcium has not been observed previously for the system [M(bidentate)2- (unidentate)4]; in the present structure, the calcium is coordinated by a pair of bidentate picrate ligands and the four water molecules in an array in which three of the water molecules occupy a triangular face of a square antiprism, the overall array having m symmetry. The remaining water molecule occupies a lattice site with no close interaction with the other species.

A novel one-dimensional CoIIcoordination polymer:catena-poly[[hexaaquacobalt(II)] [[diaquabis(sulfato-κO)cobalt(II)]-μ-4,4′-bipyridine-κ2N:N′] [[triaqua(sulfato-κO)cobalt(II)]-μ-4,4′-bipyridine-κ2N:N′]]

2012 ◽  
Vol 68 (9) ◽  
pp. m265-m268 ◽  
Author(s):  
Kai-Long Zhong ◽  
Ming-Yi Qian
Keyword(s):  
Crystal Structure ◽  
Three Dimensional ◽  
The Other ◽  
Water Molecules ◽  
Supramolecular Network ◽  
Sulfate Ion ◽  
Sulfate Ions ◽  
One Dimensional ◽  
The Third ◽  
Hydrogen Bonding Interactions

The title compound, {[Co(H2O)6][Co(SO4)(C10H8N2)(H2O)3][Co(SO4)2(C10H8N2)(H2O)2]}n, contains three crystallographically unique CoIIcentres, all of which are in six-coordinated environments. One CoIIcentre is coordinated by two bridging 4,4′-bipyridine (4,4′-bipy) ligands, one sulfate ion and three aqua ligands. The second CoIIcentre is surrounded by two N atoms of two 4,4′-bipy ligands and four O atoms,i.e.two O atoms from two monodentate sulfate ions and two from water molecules. The third CoIIcentre forms part of a hexaaquacobalt(II) ion. In the crystal structure, there are two different one-dimensional chains, one being anionic and the other neutral, and adjacent chains are arranged in a cross-like fashion around the mid-point of the 4,4′-bipy ligands. The structure features O—H...O hydrogen-bonding interactions between sulfate anions and water molecules, resulting in a three-dimensional supramolecular network.

scholarly journals Fedorite from Murun Alkaline Complex (Russia): Spectroscopy and Crystal Chemical Features

Minerals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 702
Author(s):  
Ekaterina V. Kaneva ◽  
Roman Yu. Shendrik ◽  
Tatiana A. Radomskaya ◽  
Ludmila F. Suvorova
Keyword(s):  
Crystal Structure ◽  
Emission Spectra ◽  
Chemical Study ◽  
Double Layers ◽  
Water Molecules ◽  
Crystal Chemical ◽  
Alkaline Complex ◽  
Deformation Parameters ◽  
First Time ◽  
Red Coloration

Fedorite is a rare phyllosilicate, having a crystal structure characterized by SiO4-tetrahedral double layers located between continuous layers formed by edge-sharing (Ca,Na)-octahedra, and containing interlayer K, Na atoms and H2O molecules. A mineralogical-petrographic and detailed crystal-chemical study of fedorite specimens from three districts of the Murun alkaline complex was performed. The sequence of the crystallization of minerals in association with fedorite was established. The studied fedorite samples differ in the content of interlayer potassium and water molecules. A comparative analysis based on polyhedral characteristics and deformation parameters was carried out. For the first time, EPR, optical absorption and emission spectra were obtained for fedorite. The raspberry-red coloration of the mineral specimens could be attributed to the presence of Mn4+ ions.

Darstellung und Kristallstruktur von K2Sb4S7 · H2O / Preparation and Crystal Structure of K2Sb4S7 · H2O

1979 ◽  
Vol 34 (3) ◽  
pp. 383-385 ◽  
Author(s):  
Brigitte Eisenmann ◽  
Herbert Schäfer
Keyword(s):  
Crystal Structure ◽  
Free Electron ◽  
Electron Pair ◽  
Three Dimensional ◽  
The Other ◽  
Water Molecules ◽  
Triclinic System ◽  
Dimensional Network ◽  
Free Electron Pair

Abstract K2Sb4S7 · H2O crystallizes in the triclinic system with a = 1171.4(5) pm, b = 952.0(5) pm, c = 715.6(5) pm and α = 99.36(5)°, β = 86.80(5)°, γ= 103.48(5)°. One half of the Sb atoms has three sulfur neighbours forming with the free electron pair a ψ-ShS3 tetrahedron, while the other half is coordinated by four S atoms to build a ψ-trigonal SbS4 bipyramid. These polyhedra are connected by common edges and corners to a three-dimensional network with two types of channels, in which either K+ ions only or K+ ions and water molecules are located.

The structure of reyerite, (Na,K)2Ca14Si22Al2O58(OH)8.6H2O

1988 ◽  
Vol 52 (365) ◽  
pp. 247-255 ◽  
Author(s):  
Stefano Merlino
Keyword(s):  
Crystal Structure ◽  
The Other ◽  
Water Molecules ◽  
Charge Balance ◽  
Alkali Cations ◽  
Structural Units ◽  
Tetrahedral Sheet ◽  
Space Group

AbstractThe crystal structure of reyerite, (Na,K)2Ca14Si22Al2O58(OH)8.6H2O, Z = 1, was refined in the space group P, a = 9.765, c = 19.067Å, to R = 0.064 for 1540 reflections. The structure is composed of the following structural units: (a) tetrahedral sheets S1, with composition (Si8O20)8−, characterized by six-membered rings of tetrahedra; (b) tetrahedral sheets S2, characterized by six-membered rings of tetrahedra, with six tetrahedra pointing in one direction and two pointing in the other direction—the apical oxygens of these two tetrahedra connect two inversion-related S2 sheets to build double sheets, with composition (Si14Al2O38)14− and ordered distribution of aluminum cations; (c) sheets O of edge-sharing calcium octahedra. The various structural units are connected through corner sharing according to the schematic sequence ……; the corresponding composition is [Ca14Si22Al2O58(OH)8]2−. The charge balance is restored by alkali cations which are placed, together with water molecules, in the cavities of the structure at the level of the double tetrahedral sheet.

scholarly journals Crystal structure and solvent-dependent behaviours of 3-amino-1,6-diethyl-2,5,7-trimethyl-4,4-diphenyl-3a,4a-diaza-4-bora-s-indacene

2017 ◽  
Vol 73 (3) ◽  
pp. 378-382
Author(s):  
Lijing Yang ◽  
Brett Drew ◽  
Ravi Shekar Yalagala ◽  
Rameez Chaviwala ◽  
Razvan Simionescu ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Fluorescence Spectroscopy ◽  
Title Compound ◽  
Nmr Spectra ◽  
Membered Ring ◽  
The Other ◽  
Time Dependent ◽  
H Nmr ◽  
The Mean ◽  
Over Time

In the title compound (3-amino-4,4-diphenyl-BODIPY), C28H32BN3, the central six-membered ring has a flattened sofa conformation, with one of the N atoms deviating by 0.142 (4) Å from the mean plane of the other five atoms, which have an r.m.s. deviation of 0.015 Å. The dihedral angle between the two essentially planar outer five-membered rings is 8.0 (2)°. In the crystal, molecules are linkedviaweak N—H...π interactions, forming chains along [010]. The compound displays solvent-dependent behaviours in both NMR and fluorescence spectroscopy. In the1H NMR spectra, the aliphatic resonance signals virtually coalesce in solvents such as chloroform, dichloromethane and dibromoethane; however, they are fully resolved in solvents such as dimethyl sulfoxide (DMSO), methanol and toluene. The excitation and fluorescence intensities in chloroform decreased significantly over time, while in DMSO the decrease is not so profound. In toluene, the excitation and fluorescent intensities are not time-dependent. This behaviour is presumably attributed to the assembly of 3-amino-4,4-diphenyl-BODIPY in solution that leads to the formation of noncovalent structures, while in polar or aromatic solvents, the formation of these assemblies is disrupted, leading to resolution of signals in the NMR spectra.

scholarly journals Crystal structure of dimanganese(II) zinc bis[orthophosphate(V)] monohydrate

2015 ◽  
Vol 71 (2) ◽  
pp. 154-156 ◽  
Author(s):  
Ghaleb Alhakmi ◽  
Abderrazzak Assani ◽  
Mohamed Saadi ◽  
Lahcen El Ammari
Keyword(s):  
Crystal Structure ◽  
Transition Metal ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
The Other ◽  
Water Molecules ◽  
Framework Structure ◽  
Hydrothermal Conditions ◽  
Metal Phosphates

The title compound, Mn2Zn(PO4)2·H2O, was obtained under hydrothermal conditions. The structure is isotypic with other transition metal phosphates of the typeM3−xM′x(PO4)2·H2O, but shows no statistical disorder of the three metallic sites. The principal building units are distorted [MnO6] and [MnO5(H2O)] octahedra, a distorted [ZnO5] square pyramid and two regular PO4tetrahedra. The connection of the polyhedra leads to a framework structure. Two types of layers parallel to (-101) can be distinguished in this framework. One layer contains [Zn2O8] dimers linked to PO4tetrahedraviacommon edges. The other layer is more corrugated and contains [Mn2O8(H2O)2] dimers and [MnO6] octahedra linked together by common edges. The PO4tetrahedra link the two types of layers into a framework structure with channels parallel to [101]. The H atoms of the water molecules point into the channels and form O—H...O hydrogen bonds (one of which is bifurcated) with framework O atoms across the channels.

scholarly journals Crystal structure of magnesium selenate heptahydrate, MgSeO4·7H2O, from neutron time-of-flight data

2014 ◽  
Vol 70 (9) ◽  
pp. 134-137 ◽  
Author(s):  
A. Dominic Fortes ◽  
Matthias J. Gutmann
Keyword(s):  
Crystal Structure ◽  
Unit Cell Volume ◽  
Lattice Water Molecule ◽  
Water Molecules ◽  
Tetrahedral Coordination ◽  
Flight Data ◽  
Lattice Water ◽  
Neutron Time ◽  
The Mean ◽  
Coordinated Water

MgSeO4·7H2O is isostructural with the analogous sulfate, MgSO4·7H2O, consisting of isolated [Mg(H2O)6]2+octahedra and [SeO4]2−tetrahedra, linked by O—H...O hydrogen bonds, with a single interstitial lattice water molecule. As in the sulfate, the [Mg(H2O)6]2+coordination octahedron is elongated along one axis due to the tetrahedral coordination of the two apical water molecules; these have Mg—O distances of ∼2.10 Å, whereas the remaining four trigonally coordinated water molecules have Mg—O distances of ∼2.05 Å. The mean Se—O bond length is 1.641 Å and is in excellent agreement with other selenates. The unit-cell volume of MgSeO4·7H2O at 10 K is 4.1% larger than that of the sulfate at 2 K, although this is not uniform; the greater part of the expansion is along theaaxis of the crystal.

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