On the Preparation of Good Quality X-ray Powder Patterns

For several years we have prepared and submitted a variety of quality powder x-ray diffraction patterns to the International Centre for Diffraction Data (ICDD) for inclusion as reference standards in their Powder Diffraction File (PDF). Patterns submitted and/or currently under development include metal hydrides (inorganics), flavanoids and related compounds (organics), organic compounds involved in pollution (e.g., dioxins), explosives (organics and metal organics) and glass-ceramic phases (inorganics).

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International Centre for Diffraction Data and American Society for Metals database survey of thermoelectric half-Heusler material systems

Powder Diffraction ◽

10.1017/s0885715612000942 ◽

2013 ◽

Vol 28 (1) ◽

pp. 32-43 ◽

Cited By ~ 5

Author(s):

Winnie Wong-Ng ◽

J. Yang

Keyword(s):

Phase Diagrams ◽

Powder Diffraction ◽

Diffraction Data ◽

Materials Selection ◽

Powder Diffraction File ◽

X Ray ◽

Material Systems ◽

Diffraction Patterns ◽

American Society ◽

Related Compounds

Phase diagrams and X-ray powder diffraction patterns provide critical information for thermoelectric (TE) research. We have conducted a survey of phase diagrams and powder diffraction patterns of TE systems in the ASM (American Society for Metals) Metal/Alloy database and ICDD (International Centre for Diffraction Data) PDF (Powder Diffraction File), respectively, for their availability and crystal systems. In this report, we focus on TE materials that have the half-Heusler XYZ structure, and related compounds, based on a set of materials selection rules. We found that among 306 potential XYZ compounds that we have surveyed, 234 have powder diffraction patterns in the PDF, but only 28 have phase diagram information, and 67 do not have any crystallographic information. Among the 234 phases with powder patterns, 84 were reported to have cubic F43m half-Heusler type structure, and the remainder have hexagonal, orthorhombic or other structure types. Some XYZ compounds have both cubic and hexagonal phases. This information will provide the basis for future activities for the improvement of the databases. These activities include filling the missing gaps in both phase equilibria database and the PDF, as well as adding TE and pertinent physical properties to the PDF.

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X-ray diffraction data for two new calcium uranium (VI) hydrates

Powder Diffraction ◽

10.1017/s0885715600009477 ◽

1997 ◽

Vol 12 (2) ◽

pp. 81-86 ◽

Cited By ~ 4

Author(s):

J. M. S. Skakle ◽

L. P. Moroni ◽

F. P. Glasser

Keyword(s):

Powder Diffraction ◽

Diffraction Data ◽

Unit Cell ◽

Chemical Formula ◽

X Ray Diffraction ◽

Orthorhombic Space Group ◽

Orthorhombic Unit Cell ◽

Powder Diffraction File ◽

X Ray ◽

Diffraction Patterns

The X-ray powder diffraction patterns for two new synthetic calcium uranium (VI) silicate hydrate phases are reported. Ca1.5U6(OH)7O16·7H2O is orthorhombic, space group P*a*, with unit cell a=13.8949(14), b=12.0776(12), c=15.228(3) Å. The structure appears to be related to that of becquerelite. Ca2(UO2)2(Si2O5)3·10H2O was also indexed on an orthorhombic unit cell, a=12.075(3), b=15.406(6), c=26.043(6) Å. The Powder Diffraction File coverage of uranium-containing minerals which could, on the basis of their chemical formula, form in U-containing cements is also reviewed.

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The JCPDS Data Base - Present and future

Advances in X-ray Analysis ◽

10.1154/s0376030800012313 ◽

1982 ◽

Vol 26 ◽

pp. 87-88 ◽

Cited By ~ 1

Author(s):

Winnie Wong-Ng ◽

Mark Holomany ◽

W. Frank McClune ◽

Camden R. Hubbard

Keyword(s):

Data Base ◽

Powder Diffraction ◽

Diffraction Data ◽

Scientific Data ◽

National Bureau ◽

X Ray Diffraction ◽

Data Bases ◽

Powder Diffraction File ◽

X Ray ◽

Diffraction Patterns

The Powder Diffraction File (PDF), published by the JCPDS-International Centre for Diffraction Data, is one of the most widely used scientific data bases. It currently consists of about 40,000 x-ray diffraction patterns, organized into 32 sets and 5 subfiles: metals and alloys, minerals, common phases, forensic patterns, and those from the National Bureau of Standards (NBS), New patterns are being added to the PDF at a rate of 2,000 patterns per year. The sources of these patterns are the literature, private contributions, grants in-aid projects, and the JCPDS Associateship at the NBS.

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Evaluation of Reference X-ray Diffraction Patterns in the ICDD Powder Diffraction File

Advances in X-ray Analysis ◽

10.1154/s0376030800014683 ◽

1990 ◽

Vol 34 ◽

pp. 369-376

Author(s):

G. J. McCarthy ◽

J. M. Holzer ◽

W. M. Syvinski ◽

K. J. Martin ◽

R. G. Garvey

Keyword(s):

Powder Diffraction ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

Cd Rom ◽

X Ray ◽

Binary Oxides ◽

Diffraction Patterns ◽

Input Format ◽

Good Agreement

AbstractProcedures and tools for evaluation of reference x-ray powder patterns in the JCPDSICDD Powder Diffraction File are illustrated by a review of air-stable binary oxides. The reference patterns are evaluated using an available microcomputer version of the NBS*A1DS83 editorial program and PDF patterns retrieved directly from the CD-ROM in the program's input format. The patterns are compared to calculated and experimental diffractograms. The majority of the oxide patterns have been found to be in good agreement with the calculated and observed diffractograms, but are often missing some weak reflections routinely observed with a modern diffractometer. These weak reflections are added to the PDF pattern. For the remainder of the phases, patterns are redetermined.

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The X-Ray Powder Diffraction Patterns and Crystal Structure for Al2M3Y(M=Cu, Ni)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.950.48 ◽

2014 ◽

Vol 950 ◽

pp. 48-52

Author(s):

De Gui Li ◽

Ming Qin ◽

Liu Qing Liang ◽

Zhao Lu ◽

Shu Hui Liu ◽

...

Keyword(s):

Crystal Structure ◽

Powder Diffraction ◽

Diffraction Data ◽

Hexagonal Structure ◽

Argon Atmosphere ◽

X Ray Diffraction ◽

High Quality ◽

X Ray ◽

Arc Melting ◽

Diffraction Patterns

The Al2M3Y(M=Cu, Ni) compound was synthesized by arc melting under argon atmosphere. The high-quality powder X-ray diffraction data of Al2M3Y have been presented. The refinement of the X-ray diffraction patterns for the Al2M3Y compound show that the Al2M3Y has hexagonal structure, space groupP6/mmm(No.191), with a = b = 5.1618(2) Å, c = 4.1434(1) Å,V= 95.6 Å3,Z= 1,ڑx= 5.7922 g/cm3,F30= 155.5(0.0057, 34), RIR = 2.31 for Al2Cu3Y, and with a = b = 5.0399(1) Å, c = 4.0726(1) Å,V= 89.59 Å3,Z= 1,ڑx= 5.9118 g/cm3,F30= 135.7(0.0072, 30), RIR = 2.54 for Al2Ni3Y.

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X-ray powder diffraction data for compound DyNiSn

Powder Diffraction ◽

10.1017/s088571560000957x ◽

1997 ◽

Vol 12 (3) ◽

pp. 134-135

Author(s):

Liangqin Nong ◽

Lingmin Zeng ◽

Jianmin Hao

Keyword(s):

Powder Diffraction ◽

Diffraction Data ◽

Figure Of Merit ◽

Room Temperature ◽

Unit Cell ◽

Powder Diffraction Data ◽

X Ray Diffraction ◽

Space Group ◽

X Ray ◽

Diffraction Patterns

The compound DyNiSn has been studied by X-ray powder diffraction. The X-ray diffraction patterns for this compound at room temperature are reported. DyNiSn is orthorhombic with lattice parameters a=7.1018(1) Å, b=7.6599(2) Å, c=4.4461(2) Å, space group Pna21 and 4 formula units of DyNiSn in unit cell. The Smith and Snyder Figure-of-Merit F30 for this powder pattern is 26.7(0.0178,63).

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On racemic and L-malates: a comparison of their crystal structures

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.219.2.101.26323 ◽

2004 ◽

Vol 219 (2) ◽

Cited By ~ 10

Author(s):

Michel Fleck ◽

Ekkehart Tillmanns ◽

Ladislav Bohatý ◽

Peter Held

Keyword(s):

Single Crystal ◽

Crystal Structures ◽

Powder Diffraction ◽

Diffraction Data ◽

Monoclinic Space Group ◽

Powder Diffraction Data ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

Space Group ◽

X Ray

AbstractThe crystal structures of eight different L-malates have been determined and refined from single-crystal X-ray diffraction data. The compounds are the monoclinic (space groupIn addition, for all the compounds, powder diffraction data were collected, analysed and submitted to the powder diffraction file (PDF).

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Powder X-Ray Data for Synthetic Anhydrous Sodium Zirconium Silicates

Powder Diffraction ◽

10.1017/s0885715600012653 ◽

1987 ◽

Vol 2 (3) ◽

pp. 176-179 ◽

Cited By ~ 1

Author(s):

G. Wilson ◽

F. P. Glasser

Keyword(s):

Solid State ◽

Diffraction Pattern ◽

Powder Diffraction ◽

Solid State Reaction ◽

The Other ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

X Ray ◽

Sodium Zirconium ◽

Diffraction Patterns

AbstractA systematic survey of phase formation in the Na2O-ZrO2-SiO2 system has revealed inconsistencies in the number and identity of ternary phases, and of their X-ray powder data. The phases Na2ZrSiO5, Na4Zr2Si3O12, Na2ZrSi2O7 and Na2ZrSi4O11 were prepared by solid-state reaction and their experimental X-ray diffraction patterns measured. Calculated X-ray diffraction patterns were generated by computer, using published crystallographic data, and critically compared with the experimentally observed values. The unit-cell constants were redefined to a greater accuracy than the presently accepted values published in the Powder Diffraction File. Only Na4Zr2Si3O12 produced an X-ray diffraction pattern which agreed with that previously published; those from the other phases were significantly different in both the intensities and positions of the reflections. Data for synthetic Na2ZrSi4O11 identical to the mineral vlasovite are reported.

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X-ray powder diffraction studies of (BaxSr1−x)2Co2Fe12O22 and (BaxSr1−x)Co2Fe16O27

Powder Diffraction ◽

10.1017/s0885715614001432 ◽

2015 ◽

Vol 30 (2) ◽

pp. 139-148 ◽

Cited By ~ 2

Author(s):

W. Wong-Ng ◽

G. Liu ◽

Y. Yan ◽

K. R. Talley ◽

J. A. Kaduk

Keyword(s):

Seebeck Coefficient ◽

Powder Diffraction ◽

Lattice Parameters ◽

Hexagonal Ferrite ◽

Layered Compounds ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

Space Group ◽

X Ray ◽

Diffraction Patterns

X-ray structural characterization and X-ray reference powder patterns have been determined for two series of iron- and cobalt-containing layered compounds (BaxSr1−x)2Co2Fe12O22 (x = 0.2, 0.4, 0.6, 0.8) and (BaxSr1−x)Co2Fe16O27 (x = 0.2, 0.4, 0.6, 0.8). The (BaxSr1−x)2Co2Fe12O22 series of compounds crystallized in the space group R$\bar 3$m (No. 166), with Z = 3. The structure is essentially that of the Y-type hexagonal ferrite, BaM2+Fe63+O11. The lattice parameters range from a = 5.859 15(8) to 5.843 72(8) Å, and c = 43.4975(9) to 43.3516(9) Å for x = 0.2 to 0.8, respectively. The (BaxSr1−x)Co2Fe16O27 series (W-type hexagonal ferrite) crystallized in the space group P63/mmc (No. 194) and Z = 2. The lattice parameters range from a = 5.902 05(12) to 5.8979(2) Å and c = 32.9002(10) to 32.8110(13) Å for x = 0.2 to 0.8. Results of measurements of the Seebeck coefficient and resistivity of these two sets of samples indicated that they are insulators. Powder X-ray diffraction patterns of these two series of compounds have been submitted to be included in the Powder Diffraction File.

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