NEUTRON DIFFRACTION DETERMINATION OF THE HYDROGEN POSITIONS IN NATROLITE

Neutron diffraction data obtained with single crystals of natrolite, Na2Al2Si3O10.2H20, have been analyzed using Fourier difference synthesis arid least squares methods. The details of the aluminosilicate framework were found to be in agreement with the results of earlier X-ray diffraction studies. The oxygen atom of the water molecule is linked by bent hydrogen bonds to two oxygen atoms in the framework, making an O—O—O angle of 134°. Lying almost in the O—O—O plane, the hydrogen atoms are located at distances of 0.94 ± 0.03 and 0.98 ± 0.02 Å from the oxygen of the water molecule and make with it an H—O—H angle of 108°. Natrolite thus provides an excellent example of the ability of the water molecule to resist the influence of the environment in opening the H—O—H angle.

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The structure of chromium potassium alum

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1958.0107 ◽

1958 ◽

Vol 246 (1244) ◽

pp. 78-90 ◽

Cited By ~ 34

Keyword(s):

Hydrogen Bonds ◽

Neutron Diffraction ◽

Water Molecule ◽

Water Molecules ◽

Hydrogen Atoms ◽

Potassium Alum ◽

X Ray ◽

Single Crystal Study ◽

Thermal Vibrations ◽

Oxygen Atoms

A single-crystal study of chromium potassium alum has been made by neutron diffraction, thus completing the structure first indicated by the X-ray investigations of Lipson & Beevers (1935). Hydrogen bonds link the oxygen atoms within the water molecules to other oxygen atoms in the structure. In each case the angle HOH for a water molecule is about 106°, although this sometimes entails appreciable displacement of the hydrogen atoms from the direct O—O line. Large thermal vibrations of the oxygen atoms in the sulphate groups are noteworthy.

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Hydrogen positions in potassium pentaborate tetrahydrate as determined by neutron diffraction

Canadian Journal of Physics ◽

10.1139/p70-139 ◽

1970 ◽

Vol 48 (9) ◽

pp. 1091-1097 ◽

Cited By ~ 14

Author(s):

J. P. Ashmore ◽

H. E. Petch

Keyword(s):

Neutron Diffraction ◽

Water Molecule ◽

Least Squares ◽

Single Crystals ◽

Diffraction Data ◽

Hydroxyl Groups ◽

Neutron Diffraction Data ◽

Hydrogen Atoms ◽

X Ray ◽

Atomic Coordinates

Neutron diffraction data obtained with single crystals of potassium pentaborate tetrahydrate have been analyzed using least squares methods. Apart from significant differences in the atomic coordinates of the hydrogen atoms, the structure is in agreement with recent X-ray work. The O—H distances in the hydroxyl groups are 1.012 ± 0.018 and 0.955 ± 0.020 Å. In contrast to the X-ray results, the geometry of the water molecule is normal for an inorganic hydrate with O—H distances of 0.954 ± 0.026 and 1.004 ± 0.018 Å and an H—O—H angle of 108 ± 2°.

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A powder neutron and X-ray diffraction determination of the structure of Ba3Ta2ZnO9: an investigation of perovskite phases in the system Ba–Ta–Zn–O and the preparation of Ba2TaCdO5.5and Ba2CeInO5.5

Acta Crystallographica Section B ◽

10.1107/s0567740876004718 ◽

1976 ◽

Vol 32 (4) ◽

pp. 1083-1087 ◽

Cited By ~ 75

Author(s):

A. J. Jacobson ◽

B. M. Collins ◽

B. E. F. Fender

Keyword(s):

X Ray Diffraction ◽

X Ray ◽

Diffraction Determination

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Etude structurale par diffraction des RX et spectroscopie IR des hydrates 10 et 8.4 Å de kaolinite

Journal of Applied Crystallography ◽

10.1107/s0021889899008602 ◽

1999 ◽

Vol 32 (5) ◽

pp. 968-976 ◽

Cited By ~ 5

Author(s):

S. Jemai ◽

A. Ben Haj Amara ◽

J. Ben Brahim ◽

A. Plançon

Keyword(s):

Water Molecule ◽

Octahedral Site ◽

Ammonium Fluoride ◽

Water Molecules ◽

X Ray Diffraction ◽

Tetrahedral Sheet ◽

X Ray ◽

Octahedral Sites ◽

Sheet Structure

Two hydrated kaolinites, characterized by 10 and 8.4 Å basal distances, were synthesized by treating the kaolinite KGa-1 with dimethyl sulfoxide (DMSO) and ammonium fluoride (NH4F). The X-ray diffraction study was based on a comparison between the experimental and calculated profiles. This study was conducted in two steps: firstly, the study of the 00lreflections enabled the determination of the stacking mode alongc*, the number of water molecules and their positions along the normal to the plane of the sheet structure; secondly, the study of thehkbands, withhand/ork≠ 0, enabled the determination of the stacking mode and the positions of the water molecules in the (a,b) plane. The 10 Å hydrated kaolinite is characterized by two water molecules per Al2Si2O5(OH)4unit, situated at 3 and 3.4 Å from the hydroxyl surface, over the octahedral sites. Two adjacent layers are translated with respect to each other, withT11= −0.38a− 0.37b+ 10n. The 8.4 Å hydrated kaolinite is characterized by one water molecule per Al2Si2O5(OH)4unit, situated at 2.4 Å from the hydroxyl surface and inserted between the vacant octahedral site and the ditrigonal cavity of the tetrahedral sheet. The corresponding interlayer shift isT11= −0.355a+ 0.35b+ 8.4n.

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The structure of oxide glasses studied by high-energy x-ray diffraction

Physics and Chemistry of Glasses European Journal of Glass Science and Technology Part B ◽

10.13036/17533562.61.6.kohara ◽

2020 ◽

Vol 61 (6) ◽

pp. 233-238

Author(s):

S. Kohara ◽

◽

N. Umesaki ◽

H. Ohno ◽

K. Suzuya ◽

...

Keyword(s):

Neutron Diffraction ◽

Structural Information ◽

Structural Models ◽

High Energy ◽

Reverse Monte Carlo ◽

Oxide Glasses ◽

Neutron Diffraction Data ◽

X Ray Diffraction ◽

X Ray ◽

Approaches To Study

The use of high‑energy x‑ray diffraction techniques with the latest generation synchrotron sources has created new approaches to study quantitatively the structure of noncrystalline materials. Recently, this technique has been combined with neutron diffraction at pulsed source to provide more detailed and reliable structural information not previously available. This article reviews and summarises recent results obtained from the high energy x‑ray diffraction on several oxide glasses, SiO2, B2O3 and PbSiO3, using bending magnet beamlines at SPring‑8. In particular, it addresses the structural models of the oxide glasses obtained by the reverse Monte Carlo (RMC) modelling technique using both the high energy x‑ray and neutron diffraction data.

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Practice for X-ray Diffraction Determination of Phase Content of Plasma-Sprayed Hydroxyapatite Coatings

10.1520/f2024-10r21 ◽

2021 ◽

Author(s):

Keyword(s):

Phase Content ◽

X Ray Diffraction ◽

X Ray ◽

Hydroxyapatite Coatings ◽

Diffraction Determination ◽

Plasma Sprayed

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

Zeitschrift für Naturforschung B ◽

10.1515/znb-2000-0609 ◽

2000 ◽

Vol 55 (6) ◽

pp. 495-498 ◽

Cited By ~ 11

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.

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X-ray diffraction determination of a semiconductor epilayer unit cell oriented and distorted arbitrarily

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/26/4a/038 ◽

1993 ◽

Vol 26 (4A) ◽

pp. A181-A187 ◽

Cited By ~ 5

Author(s):

B F Usher ◽

G W Smith ◽

S J Barnett ◽

A M Keir ◽

A D Pitt

Keyword(s):

Unit Cell ◽

X Ray Diffraction ◽

X Ray ◽

Diffraction Determination

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X-Ray Diffraction Determination of Metallurgical Damage in Turbo Blower Rotor Shafts

MRS Proceedings ◽

10.1557/proc-142-171 ◽

1988 ◽

Vol 142 ◽

Author(s):

John F. Porter ◽

Dan O. Morehouse ◽

Mike Brauss ◽

Robert R. Hosbons ◽

John H. Root ◽

...

Keyword(s):

Residual Stress ◽

Hole Drilling ◽

X Ray Diffraction ◽

X Ray ◽

Turbo Blower ◽

Diffraction Determination ◽

Defence Research ◽

Stress Profiles ◽

Non Destructive

AbstractStudies have been ongoing at Defence Research Establishment Atlantic on the evaluation of non-destructive techniques for residual stress determination in structures. These techniques have included neutron diffraction, x-ray diffraction and blind-hole drilling. In conjunction with these studies, the applicability of these procedures to aid in metallurgical and failure analysis investigations has been explored. The x-ray diffraction technique was applied to investigate the failure mechanism in several bent turbo blower rotor shafts. All examinations had to be non-destructive in nature as the shafts were considered repairable. It was determined that residual stress profiles existed in the distorted shafts which strongly indicated the presence of martensitic microstuctures. These microstructures are considered unacceptable for these shafts due to the potential for cracking or in-service residual stress relaxation which could lead to future shaft distortion.

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