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

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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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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Structures and X-ray diffraction patterns of compounds in the Sr–Nd–Cu–O system

Powder Diffraction ◽

10.1017/s0885715600014317 ◽

1995 ◽

Vol 10 (1) ◽

pp. 56-66 ◽

Cited By ~ 1

Author(s):

Winnie Wong-Ng

Keyword(s):

Crystal Structures ◽

Powder Diffraction ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

Comprehensive Review ◽

X Ray ◽

Diffraction Patterns ◽

Ternary Oxides

A comprehensive review of phases found in the Sr–Nd–Cu–O system which contains the high Tc superconductor phase Sr1−xNdxCuO2 has been prepared. This paper summarizes the crystal structures reported in the literature and the X-ray powder diffraction patterns reported in the ICDD Powder Diffraction File (PDF). In order to supplement the PDF with new patterns, calculated X-ray powder diffraction patterns generated from reported structures are provided for five ternary oxides: Sr0.86Nd0.14CuO2, SrNdCuO3.5, Sr6Nd3Cu6O17, Sr2NdCu2O5.66, and Sr1.2Nd1.8Cu2O6.

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The Quality of X-ray Diffraction Standards for Phosphate Minerals and the Degree of Success in Computer Identification

Advances in X-ray Analysis ◽

10.1154/s0376030800014129 ◽

1984 ◽

Vol 28 ◽

pp. 305-308

Author(s):

Frank N. Blanchard

Keyword(s):

Data Base ◽

Powder Diffraction ◽

Data Reduction ◽

Phase Identification ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

X Ray ◽

Diffraction Patterns ◽

Computer Identification

Sixty-five years ago Hull first described X-ray powder diffraction as a means of phase identification, and 45 years ago Hannawalt and co-workers compiled the first catalogue of powder diffraction patterns, which has evolved into a file of about 44,000 patterns (the X-ray Powder Diffraction File or PDF). The Hannawalt method of manually searching the PDF is a time-tested, effective tool in seeking a match between an unknown pattern and its correct counterpart(s) in the PDF. Recently, computerized powder diffractometers with software to perform data reduction and search the PDF have become relatively common, and these systems offer tremendous potential for rapid and accurate phase identification in simple and complex systems where the data base may include 44,000 patterns.

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Computer Identification Techniques for Crystalline Compounds Using the JCPDS Powder Diffraction File as a Data Reference

Advances in X-ray Analysis ◽

10.1154/s0376030800011745 ◽

1976 ◽

Vol 20 ◽

pp. 103-112

Author(s):

George Van Trump ◽

Phoebe L. Hauff

Keyword(s):

Data Base ◽

Powder Diffraction ◽

Time Sharing ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

X Ray ◽

Jcpds Powder Diffraction File ◽

Diffraction Patterns ◽

Identification Techniques ◽

Computer Identification

The mineralogy laboratory of the U.S. Geological Survey in Denver has developed a series of time-sharing oriented computer programs which aid in the identification of crystalline compounds from chemical and X-ray diffraction data. These programs operate on a data base compiled primarily from the Powder Diffraction File of the Joint Committee on Powder Diffraction Standards (JCPDS). Diagrammatic X-ray diffraction patterns and various search tables are products of these programs. Additional programs can retrieve information from the data base by chemical formula components or Powder Diffraction File number, and can search and match reflections of an unknown against reference patterns.

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Crystal structures and reference X-ray powder diffraction patterns of Sr4−xCaxPb2O8 (x=1,2,3)

Powder Diffraction ◽

10.1017/s0885715600010162 ◽

1998 ◽

Vol 13 (4) ◽

pp. 232-240 ◽

Cited By ~ 1

Author(s):

W. Wong-Ng ◽

J. A. Kaduk ◽

W. Greenwood

Keyword(s):

Crystal Structure ◽

Solid Solution ◽

Crystal Structures ◽

Powder Diffraction ◽

Alkaline Earth ◽

Lattice Parameters ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

X Ray ◽

Diffraction Patterns

The crystal structure of the solid solution alkaline earth plumbate phase Sr4−xCaxPb2O8 was investigated using the X-ray Rietveld technique for x=1, 2, and 3. The lattice parameters a, b, c, and V were found to decrease linearly as the Sr at site 4h was replaced by Ca. The structure features chains of edge-sharing PbO6 octahedra, linked by seven-coordinated (Ca/Sr)–O monocapped trigonal prisms. The structure is similar to that of Pb3O4, which can be reformulated as Pb2IIPbIVO4. X-ray diffraction patterns for the solid solution members SrCa3Pb2O8, Sr2Ca2Pb2O8, and Sr3CaPb2O8 were prepared for inclusion in the Powder Diffraction File.

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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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X-ray powder reference patterns for magnetoplumbite-like compounds, (BaxSr1−x)Ti6Co6O19 (x = 0.2, 0.4, 0.6, 0.8)

Powder Diffraction ◽

10.1017/s0885715615000469 ◽

2015 ◽

Vol 30 (3) ◽

pp. 256-262

Author(s):

W. Wong-Ng ◽

G. Liu ◽

J. A. Kaduk

Keyword(s):

Powder Diffraction ◽

Alkaline Earth ◽

X Ray Diffraction ◽

Powder Diffraction File ◽

X Ray ◽

Octahedral Sites ◽

Tetrahedral Sites ◽

The Face ◽

Structural Isomorphism ◽

Diffraction Patterns

X-ray reference powder patterns and crystal structures have been determined for a series of titanium- and cobalt-containing layered alkaline-earth compounds with nominal formula (BaxSr1−x)Ti6Co6O19 (x = 0.2, 0.4, 0.6, 0.8). Structural isomorphism of the title compounds with the hexagonal ferrite BaFe12O19 and magnetoplumbite (PbFe12O19), was confirmed. The (BaxSr1−x)Ti6Co6O19 series crystallize in the space group of P63/mmc (No. 194) and Z = 2. The lattice parameters range from a = 5.90729(6) Å, c = 23.2378(3) Å, and V = 702.27(2) Å3 for x = 0.2 to a = 5.914 93(9), c = 23.3391(5) Å, and V = 707.15(2) Å3 with x = 0.8. The structure consists of alternating spinel S-block and R-blocks. The tetrahedral sites within the spinel S-blocks are occupied with only Co2+, while Ti4+ is mainly located in the octahedral sites of the spinel S-blocks and in the face-sharing octahedral site of the R-blocks. A bipyramidal mixed Co/Ti site was confirmed in the R-block of the structure. Powder X-ray diffraction patterns of this series of compounds have been submitted to be included in the Powder Diffraction File.

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Crystal chemistry and X-ray diffraction patterns for Co(NixZn1−x)Nb4O12(x= 0.2, 0.4, 0.6, 0.8)

Powder Diffraction ◽

10.1017/s0885715616000531 ◽

2016 ◽

Vol 31 (4) ◽

pp. 279-284

Author(s):

G. Liu ◽

W. Wong-Ng ◽

J. A. Kaduk

Keyword(s):

Crystal Chemistry ◽

Powder Diffraction ◽

Type Structure ◽

X Ray Diffraction ◽

Single Chain ◽

Powder Diffraction File ◽

Space Group ◽

X Ray ◽

Cobalt Nickel ◽

Diffraction Patterns

X-ray reference powder patterns and structures have been determined for a series of cobalt-, nickel- and zinc-containing niobates, Co(NixZn1−x)Nb4O12(x= 0.2, 0.4, 0.6, 0.8). The Co(NixZn1−x)Nb4O12series crystallize in the space group ofPbcn, which is of the disordered columbite-type structure (α-PbO2). The lattice parameters range froma= 14.11190(13) to 14.1569(3) Å,b= 5.69965(6) to 5.71209(13) Å,c= 5.03332(5) to 5.03673(11) Å, andV= 404.844(8) to 407.296(17) Å3fromx= 0.8 to 0.2, respectively. Co(NixZn1−x)Nb4O12contains double zig-zag chains of NbO6octahedra and single chain of (Ni,Zn,Co)O6octahedra run parallel to thebc-plane. Within the same chain the NbO6octahedra share edges, while the adjacent NbO6chains are joined to each other through common oxygen corners. These double NbO6chains are further linked together along the [100]-direction through another (Co,Ni,Zn)O6units, via common oxygen corners. The edge-sharing (Co,Ni,Zn)O6also forms zig-zag chains along thec-axis. Powder X-ray diffraction patterns of this series of compounds have been submitted to be included in the Powder Diffraction File.

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