Variation of the intensity of reflected X-radiation with the temperature of the crystal

On account of the increasing importance of the temperature factor in the theory of the analysis of crystal structure by means of X-ray reflection, and in view of the fact that no experimental work on the temperature effect has been published since the original preliminary investigation by Prof. W. H. Bragg in 1914, it is hoped that the present account will be of interest, in which the work of Bragg is extended to a variety of crystals and continuous temperature curves have been obtained ranging up to 950°C. Theories of the effect of temperature on X-ray reflection have been given by C. G. Darwin and P. Debye, and these agree in that the intensity of reflection— (1) Decreases as the temperature of the crystal increases; (2) Decreases more rapidly as the angle of reflection increases.

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The Crystalline Monitoring of Oxide Compound: The Case Study of Influence from Heat Treatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.770.311 ◽

2013 ◽

Vol 770 ◽

pp. 311-314

Author(s):

P. Kuha ◽

K. Teanchai ◽

S. Kongsriprapan ◽

Wichian Siriprom

Keyword(s):

Crystal Structure ◽

Amorphous Structure ◽

Effect Of Temperature ◽

Natural Material ◽

Oxide Compound ◽

X Ray ◽

Babylonia Areolata ◽

Air Atmosphere ◽

Ft Ir ◽

The Relationship

In present study, the structural and thermal characterizations of the natural material were investigated, the relationship between the crystal structure and thermal treatment were studied. The relationship between temperature and features of the crystal structure were determined qualitative by three conventional analysis techniques, X-Ray Diffraction (XRD), Energy Dispersive X-Ray Fluorescence (EDXRF) and Fourier Transform Infrared Spectroscopy (FT-IR). The results show that theBabylonia areolatahave a crystalline of calcium carbonate in phase aragonite, and the rice husks have amorphous structure. Another that, both sample annealed under air atmosphere, the effect of temperature induced both materials have phase transformation. Both sample transformed into oxide compound at temperature about 900C. In addition, the composition of both mineral and the level of the metals element were investigated by EDXRF. Functional group and chemical environment of silicon ions and calcium ions were identified by FT-IR, respectively.

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A study on α-RuCl3 crystal structure by scanning tunneling microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152124 ◽

1989 ◽

Vol 47 ◽

pp. 30-31

Author(s):

H.-J. Cantow ◽

H. Hillebrecht ◽

S. Magonov ◽

H. W. Rotter ◽

G. Thiele

Keyword(s):

Crystal Structure ◽

Density Distribution ◽

Scanning Tunneling Microscopy ◽

Electron Density ◽

Structure Determination ◽

Electron Density Distribution ◽

Scanning Tunneling ◽

Monoclinic Space Group ◽

Tunneling Microscopy ◽

X Ray

From X-ray analysis, the conclusions are drawn from averaged molecular informations. Thus, limitations are caused when analyzing systems whose symmetry is reduced due to interatomic interactions. In contrast, scanning tunneling microscopy (STM) directly images atomic scale surface electron density distribution, with a resolution up to fractions of Angstrom units. The crucial point is the correlation between the electron density distribution and the localization of individual atoms, which is reasonable in many cases. Thus, the use of STM images for crystal structure determination may be permitted. We tried to apply RuCl3 - a layered material with semiconductive properties - for such STM studies. From the X-ray analysis it has been assumed that α-form of this compound crystallizes in the monoclinic space group C2/m (AICI3 type). The chlorine atoms form an almost undistorted cubic closed package while Ru occupies 2/3 of the octahedral holes in every second layer building up a plane hexagon net (graphite net). Idealizing the arrangement of the chlorines a hexagonal symmetry would be expected. X-ray structure determination of isotypic compounds e.g. IrBr3 leads only to averaged positions of the metal atoms as there exist extended stacking faults of the metal layers.

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X-ray Crystal Structure of ?9-THC-tosylate

Planta Medica ◽

10.1055/s-2008-1075216 ◽

2008 ◽

Vol 74 (03) ◽

Author(s):

W Gul ◽

P Carvalho ◽

D Slade ◽

M Avery ◽

JR Duchek ◽

...

Keyword(s):

Crystal Structure ◽

X Ray

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Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.218.5.381.20734 ◽

2003 ◽

Vol 218 (5) ◽

Cited By ~ 5

Author(s):

Süheyla Özbey ◽

F. B. Kaynak ◽

M. Toğrul ◽

N. Demirel ◽

H. Hoşgören

Keyword(s):

Crystal Structure ◽

Inclusion Complex ◽

Single Crystal ◽

X Ray Diffraction ◽

Space Group ◽

X Ray ◽

New Type

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group

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Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

10.26434/chemrxiv.11345063.v2 ◽

2020 ◽

Author(s):

Keishiro Yamashita ◽

Kazuki Komatsu ◽

Hiroyuki Kagi

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Crystal Growth ◽

Single Crystal ◽

Room Temperature ◽

Growth Technique ◽

Salt Hydrate ◽

X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

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