The X-ray structure of a sodium peroxide hydrate, Na2O2•8H2O, and its reactions with carbon dioxide: relevance to the brightening of mechanical pulps

1997 ◽  
Vol 75 (1) ◽  
pp. 46-51 ◽  
Author(s):  
Geoffrey S. Hill ◽  
David G. Holah ◽  
Stephen D. Kinrade ◽  
Todd A. Sloan ◽  
Vincent R. Magnuson ◽  
...  
Keyword(s):  
Water Molecules ◽  
Monoclinic Space Group ◽  
Sodium Peroxide ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mechanical Pulps ◽  
Main Component ◽  
Key Words Sodium ◽  
Centrosymmetric Structure ◽  
Oxygen Atoms

The main component of the solid originally believed to be a peroxosilicate with pulp-brightening properties has been shown to be Na2O2•8H2O. The solid crystallizes in the monoclinic space group C2/c, with an empirical formula H8O5Na, and with a = 14.335(3), b = 6.461(1), c = 11.432(2) Å, β = 118.28(3)°, and Z = 8. The centrosymmetric structure consists of a peroxide anion with an O—O distance of 1.499(2) Å. Each of these oxygen atoms is at the apex of an approximate square-based pyramid, the base of which consists of four oxygen atoms of water molecules. The bases of the two pyramids are staggered when viewed down the peroxide bond. Each sodium is at the centre of an approximate octahedron of water molecules, four of which bridge other sodium atoms and two bridge to the peroxide anions. One hydrogen atom of each of these two water molecules is terminal and the other two are hydrogen bonded to peroxide oxygen atoms. The compound reacts very rapidly with CO2 in moist air to form Na2CO3, but in drier conditions, formation of the carbonate can take many days and proceeds via a percarbonate, believed to be Na2CO4. This has been identified by infrared spectroscopy and X-ray powder diffraction and can persist for long periods in dry air. Key words: sodium peroxide hydrate, sodium percarbonate, pulp brightening, X-ray diffraction, infrared.

scholarly journals Synthesis and Complexation Properties of 2-Hydroxy-5-methoxyphenylphosphonic Acid (H3L1). Crystal Structure of the [Cu(H2L1)2(Н2О)2] Complex

2021 ◽  
Vol 91 (11) ◽  
pp. 2176-2186
Author(s):  
G. S. Tsebrikova ◽  
Yu. I. Rogacheva ◽  
I. S. Ivanova ◽  
A. B. Ilyukhin ◽  
V. P. Soloviev ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Methoxy Group ◽  
Protonation Constants ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Stability ◽  
Intramolecular Hydrogen ◽  
Oxygen Atoms

Abstract 2-Hydroxy-5-methoxyphenylphosphonic acid (H3L1) and the complex [Cu(H2L1)2(H2O)2] were synthesized and characterized by IR spectroscopy, thermogravimetry, and X-ray diffraction analysis. The polyhedron of the copper atom is an axially elongated square bipyramid with oxygen atoms of phenolic and of monodeprotonated phosphonic groups at the base and oxygen atoms of water molecules at the vertices. The protonation constants of the H3L1 acid and the stability constants of its Cu2+ complexes in water were determined by potentiometric titration. The protonation constants of the acid in water are significantly influenced by the intramolecular hydrogen bond and the methoxy group. The H3L1 acid forms complexes CuL‒ and CuL24‒ with Cu2+ in water.

Carbacylamidophosphates: Synthethis and Structure of N,N'-Tetramethyl-NM-benzoylphosphoryltriamide and Dimorpholido-N-benzoylphosphorylamide

2000 ◽  
Vol 55 (6) ◽  
pp. 495-498 ◽  
Author(s):  
Katerina E. Gubina ◽  
Vladimir A. Ovchynnikov ◽  
Vladimir M. Amirkhanov ◽  
Viktor V. Skopenkoa ◽  
Oleg V. Shishkinb
Keyword(s):  
Nmr Spectroscopy ◽  
Hydrogen Bonds ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
Sodium Salts ◽  
Space Group ◽  
X Ray ◽  
Centrosymmetric Dimers ◽  
Oxygen Atoms

N,N′-Tetramethyl-N"-benzoylphosphoryltriamide (I) and dimorpholido-N-benzoylphosphorylamide (II), and their sodium salts Nal, Nall were synthesized and characterized by means of IR and 1H, 31P NMR spectroscopy. The structures of I, II were determined by X-ray diffraction: I monoclinic, space group P2i/c with a = 10.162(3), b= 11.469(4), c = 12.286(4) Å , β = 94.04°, V = 1428.4(8) A 3, Z = 4, p(calcd) = 1.187 g/cm3; II monoclinic, space group C2/c with a = 15.503(4), b = 10.991(3), c = 22.000(6) Å, β = 106.39°, V = 3596.3(17) Å3, Z = 8, p(calcd.) = 1.253 g/cm3. The refinement of the structures converged at R = 0.0425 for I, and R = 0.068 for II. In both structures the molecules are connected into centrosymmetric dimers via hydrogen bonds formed by the phosphorylic oxygen atoms and hydrogen atoms of amide groups.

Synthesis and Crystal Structure of a Caesium Hydrogen Benzoylcyanoximate Complex with 18-Crown-6: Cs(18-Crown-6){H(L)2}

1997 ◽  
Vol 52 (8) ◽  
pp. 901-905 ◽  
Author(s):  
Vera V Ponomareva ◽  
Victor V Skopenko ◽  
Konstantin V Domasevitch ◽  
Joachim Sieler ◽  
Thomas Gelbrich
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Crown Ether ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
The Mean ◽  
Cyano Groups ◽  
Oxygen Atoms

Abstract The caesium hydrogen benzoylcyanoximate (L-) complex with 18-crown-6 of composition Cs(18-crown-6){H(L)2} has been prepared and studied by means of X-ray diffraction [monoclinic, space group P21/n, with a = 9.906(1), b = 18.387(3), c = 18.855(3)Å, β = 90.13(1)°, V = 3434.3(9) Å, Z = 4; final R1 = 0.043 for the 6431 independent reflections used. The lattice consists of Cs(18-crown-6)+ cations and complex hydrogen oximate anions {H(L)2}-, formed via strong hydrogen bonding between the oxygen atoms of nitroso-groups [O - - - O ca. 2.456(5)Å]. The caesium atom deviates by 1.492(3) Å from the mean plane of the oxygen atoms of the macrocyclic ether (dominant orientation of disordered ligand, 60%) and adopts a typical “sunrise coordination” [Cs-O (ether) 3.040(9)-3.312(7) Å]. The hydrogen oximate groups are bonded to the metal center only on one side of the crown ether plane via the oxygen atoms of nitroso-groups and the nitrogen atoms of cyano groups (Cs-O ca. 3.040(9), 3.312(7) Å; Cs-N ca. 3.469(5), 3.679(6) Å). The coordination polyhedron of Cs+ can be described as a distorted bicapped tetragonal prism.

scholarly journals A New 3D Coordination Polymer of Bismuth with Nicotinic AcidN-Oxide

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Farzin Marandi ◽  
Ingo Pantenburg ◽  
Gerd Meyer
Keyword(s):  
Crystal Structure ◽  
Thermal Stability ◽  
Coordination Polymer ◽  
Three Dimensional ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Thermal Stability Of

The new three-dimensional coordination polymer {[Bi(NNO)2(NO3)]·1.5H2O}n(1, NNO−= nicotinateN-oxide) was synthesized and characterized by elemental analysis, IR and1H-NMR spectroscopy, as well as single-crystal X-ray diffraction analysis.1crystallizes in the monoclinic space group C2/c. The crystal structure consists of a rectangular-shaped grid constructed with NNO linkers. Cavities of a diameter of 7.9–8.3 Å2are filled with disordered water molecules. The thermal stability of the compound was evaluated by thermogravimetric analysis.

scholarly journals X-ray structure of 1D-coordination polymer of copperII bearing 1,4-pyrazine-2,3-dicarboxylic acid and 2-aminopyrimidine

2012 ◽  
Vol 77 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Masoud Mirzaei ◽  
Hossein Eshtiagh-Hosseini ◽  
Azam Hassanpoor ◽  
Victor Barba
Keyword(s):  
Coordination Polymer ◽  
Dicarboxylic Acid ◽  
Supramolecular Assembly ◽  
Axial Position ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Double Chain ◽  
X Ray ◽  
1D Coordination Polymer ◽  
Oxygen Atoms

The new 1D-coordination polymer of CuII ion, {(2- apymH)2[Cu(pyzdc)2] .6H2O}n, (2-apym = 2-aminopyrimidine, pyzdcH2 = 1,4- pyrazine-2,3-dicarboxylic acid), was synthesized based on proton transfer mechanism and characterized by elemental analysis, infrared spectroscopy, and single crystal X-ray diffraction. The coordination polymer consists of infinite anionic chains of [Cu(pyzdc)2]2- anion bridged crossing double chain running along a-axis and discrete (2-apymH)+ fragment. The CuII ion is located on inversion centre in the basal plane of an elongated octahedron and two oxygen atoms from adjacent (pyzdc)2-ligands occupy axial position. The interaction between oxygen atoms of water molecules along with the dicarboxylic acid play an important role in the overall supramolecular assembly.

Preparation, infrared spectra, and crystal structure of two modifications of the (thymidinato-N3)methylmercury(II) complex

1985 ◽  
Vol 63 (12) ◽  
pp. 3456-3463 ◽  
Author(s):  
France Guay ◽  
André L. Beauchamp
Keyword(s):  
Infrared Spectra ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Hydroxyl Groups ◽  
Carbonyl Groups ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Preparation Conditions

Reaction of CH3HgOH with thymidine (HT) yielded the neutral CH3HgT complex crystallizing as a hydrated or an anhydrous material, depending on preparation conditions. Both forms were examined by X-ray diffraction. The anhydrous variety is monoclinic, space group P21, a = 4.798(6), b = 14.270(8), c = 10.390(4) Å, β = 102.74(9)°, and Z = 2 molecules per cell. The structure was refined on 1552 nonzero MoKα reflections to a conventional R factor of 0.034. The hydrated form belongs to the orthorhombic space group P212121, a = 10.484(3), b = 14.633(3), c = 18.538(5), Z = 8. The structure was refined on 1816 nonzero MoKα reflections to R = 0.036. In both forms, the CH3Hg+ ion is linearly bonded to the deprotonated N(3) site of thymidine. The water molecules and hydroxyl groups in the ribose unit participate in a hydrogen bonding network, in which the carbonyl groups are involved as acceptors. The infrared spectra of the two forms differ significantly only by the absorptions due to the water molecules. By comparing with the spectrum of thymidine, diagnostic regions for complexation with deprotonated thymidine have been proposed

The crystal structures of sjögrenite and pyroaurite

1967 ◽  
Vol 36 (280) ◽  
pp. 465-479 ◽  
Author(s):  
L. Ingram ◽  
H. F. W. Taylor
Keyword(s):  
Crystal Structures ◽  
Three Dimensional ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Approximate Composition ◽  
Oxygen Atoms

SummaryThe crystal structures of sjögrenite and pyroaurite, two stacking modifications of approximate composition Mg6Fe2(OH)16(CO3).4H2O, have been determined by X-ray diffraction using three-dimensional methods. Sjögrenite is hexagonal, with a 3·13, c 15·66 Å, space group P63/mmc , Z = ¼; pyroaurite is rhombohedral, with aH 3·13, cH 23·49 Å, space group R3̄m or R3m, Z = ⅜. Both structures are based on brucite-like layers, with magnesium and iron distributed among the octahedral positions. The cations appear to be largely disordered, although ordered regions may occur in some crystals. Between the brucite-like layers are the water molecules and carbonate groups. These are statistically arranged, with their oxygen atoms distributed among a larger number of possible sites.

scholarly journals On the Structure in Aqueous Superconcentrated Calcium Nitrate

1981 ◽  
Vol 36 (8) ◽  
pp. 831-835 ◽  
Author(s):  
R. Caminiti ◽  
A. Musinu ◽  
G. Paschina ◽  
G. Piccaluga ◽  
G. Pinna
Keyword(s):  
Experimental Data ◽  
Calcium Ions ◽  
Calcium Nitrate ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystalline Hydrates ◽  
Oxygen Atoms

Abstract Liquid hydrous calcium nitrate of composition Ca(NO3)2 · 3.5 H2O was investigated by X-ray diffraction. Experimental data were interpreted in terms of geometrical models suggested by the structure of the crystalline hydrates Ca (NO3)2 · 3H2O and Ca(NO3)2 · 4H2O, in which calcium ions are coordinated to nine oxygen atoms, partly coming from water molecules, partly from NO3-ions.

scholarly journals Synthesis, Structural Characterization, and Antibacterial Activity of Novel Erbium(III) Complex Containing Antimony

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Ting Liu ◽  
Rong-Gui Yang ◽  
Guo-Qing Zhong
Keyword(s):  
Ethylenediaminetetraacetic Acid ◽  
Antimicrobial Activities ◽  
Diffusion Method ◽  
Water Molecules ◽  
Equatorial Position ◽  
X Ray Diffraction ◽  
Monoclinic System ◽  
Adjacent Layer ◽  
X Ray ◽  
Oxygen Atoms

The novel 3D edta-linked heterometallic complex [Sb2Er(edta)2(H2O)4]NO3·4H2O (H4edta = ethylenediaminetetraacetic acid) was synthesized and characterized by elemental analyses, single-crystal X-ray diffraction, powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermal analysis. The complex crystallizes in the monoclinic system with space group Pm. In the complex, each erbium(III) ion is connected with antimony(III) ions bridging by four carboxylic oxygen atoms, and in each [Sb(edta)]− anion, the antimony(III) ion is hexacoordinated by two nitrogen atoms and four oxygen atoms from the edta4− ions, together with a lone electron pair at the equatorial position. The erbium(III) ion is octacoordinated by four oxygen atoms from four different edta4− ions and four oxygen atoms from the coordinated water molecules. The carboxylate bridges between antimony and erbium atoms form a planar array, parallel to the (1 0 0) plane. There is an obvious weak interaction between antimony atom and oxygen atom of the carboxyl group from the adjacent layer. The degradation of the complex proceeds in several steps and the water molecules and ligands are successively emitted, and the residues of the thermal decomposition are antimonous oxide and erbium(III) oxide. The complex was evaluated for its antimicrobial activities by agar diffusion method, and it has good activities against the test bacterial organisms.

scholarly journals Synthesis and Structural Characterization of the Tetranuclear Iron(Iii) Cluster with Salicylic Acid

2020 ◽  
Vol 15 (2) ◽  
pp. 62-68
Author(s):  
Viorina Gorinchoy
Keyword(s):  
Salicylic Acid ◽  
Diffraction Analysis ◽  
Structural Characterization ◽  
Spectroscopic Method ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ir Spectroscopic ◽  
Oxygen Atoms

A new tetra-homonuclear iron(III) cluster, [Fe4O2(Sal)4(H2O)6]·4DMA·0.75H2O, where Sal= salicylic acid and DMA= N,N-dimethylacetamide consolidated via two µ3-oxo- and four salicylate-bridges was synthesized and characterized by IR spectroscopic method as well as by single crystal X-ray diffraction analysis. The structure of the obtained tetranuclear compound consists of four FeIII atoms in a “butterfly” arrangement. The coordination sphere of each of the two central FeIII atoms is generated by two μ3-oxo-bridging atoms and four oxygen atoms provided by the tridentate-bridging Sal2- ligands, while the coordination polyhedron of another two iron atoms involve six oxygen atoms from three water molecules, two salicylic and one μ3-oxigen atom. The Fe-O distances within Fe-O-Fe bridge are of 2.102(3) Å (for wing-body) and 2.038(3) Å (for body-body).

Sign in / Sign up

Export Citation Format

Share Document