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Journal articles on the topic 'X-Ray powder Diffraction (XRD)'

Author: Grafiati

Published: 4 June 2021

Last updated: 8 February 2022

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1

Kerner, Jonathan A., Edward D. Franco, and John Marshall. "Combined XRD and XRF Analysis for Portable and Remote Applications." Advances in X-ray Analysis 38 (1994): 319–24. http://dx.doi.org/10.1154/s037603080001795x.

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Abstract A prototype instrument, which provides x-ray powder diffraction and x-ray fluorescence analysis in a compact unit, has been developed to support the needs of NASA for planetary exploration. The instrument uses a 9-watt Fe-anodc x-ray tube and CCD in a fixed geometry for recording powder patterns with a 2θ range of 35°. The fluorescence spectrum for elements below Fe is collected simultaneously with the diffraction data. A shuttered Cd-109 isotopic source with emissions at 22 and 80 keV is used to excite higher energy fluorescence. The low-energy limit for discriminating single photon events was found to be ∼1.5 keV. Al-K could be distinguished from a pure sample, but the spectrum below 6 keV was degraded by the read noise of the CCD, which introduced spectral artifacts. Diffraction peaks from halite had a FWHM of ∼1°(2θ), with major contributions to the width from the use of slit collimation on the source and the low tilt angle of the sample.

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2

Koster, Herman. "X-ray powder diffraction data for In3.85Zr2.80Sn0.35O12." Powder Diffraction 18, no. 1 (March 2003): 38–41. http://dx.doi.org/10.1154/1.1446862.

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X-ray powder diffraction data for In3.85Zr2.80Sn0.35O12 are reported. The powders were prepared using a wet-chemical precipitation method. The XRD data could be fitted with a rhombohedral unit cell in space group R3 (No. 148). The Rietveld refined unit cell parameters are a=0.951 49(2) nm and c=0.889 51(2)nm in a hexagonal setting with Z=3 and Dx=6.69(1)g/cm3.

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3

Rodriguez, Mark A., James J. M. Griego, Harlan J. Brown-Shaklee, Mia A. Blea-Kirby, John F. Ihlefeld, and Erik D. Spoerke. "X-ray powder diffraction study of La2LiTaO6." Powder Diffraction 30, no. 1 (November 21, 2014): 57–62. http://dx.doi.org/10.1017/s0885715614001183.

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The structure of La2LiTaO6 has been derived from the powder X-ray powder diffraction (XRD) data. La2LiTaO6 is monoclinic with unit-cell parameters a = 5.621(1) Å, b = 5.776(1) Å, c = 7.954(2) Å, β = 90.34(2)°, space group P21/n (14), and Z = 2. The structure of La2LiTaO6 is an ordered perovskite with alternating Li and Ta octahedra. A new set of powder XRD data (d-spacing and intensity listing) has been generated to replace entry 00-039-0897 within the Powder Diffraction File. The newly elucidated structural data for La2LiTaO6 shall facilitate quantitative analysis of this impurity phase which is often observed during synthesis of the fast-ion conductor phase Li5La3Ta2O12.

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4

Patel, Ishverbhai, and Sneha Solanki. "XRD Studies of Synthesized Bi2S3Crystalline Materials." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C508. http://dx.doi.org/10.1107/s2053273314094911.

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Bismuth sulfide preparation and its x-ray diffraction studies are reported in this paper. The author have synthesized Bi2Sx (x = 3.15, 3.45) compound material with different sulfur content by conventional high temperature solid state solvothermal reaction of bismuth and sulfur which conforms that the (121) preferred orientation with crystallite size ~30 nm and splitting of peaks due to orthorhombic structure matches well with the standard data and demonstrate good crystalline quality and structural homogeneity of synthesized powder.This paper also describes the synthesis and x-ray diffraction studies of bismuth sulfide powder via versatile precipitation technique . Bismuth sulfide powder was synthesized using thiourea and sodium dodecyl sulfate or in absence of any surfactant maintained at 800C for 12 h keeping pH of solution constant at 1.4. Synthesized powder was characterized by x-ray diffraction technique which indicates that surfactants play major role in synthesis of bismuth sulfide that conforms the crystallite size ~35 nm. The employed solid state solvothermal technique played an important role to progress the homogeneous reaction and preparation of pure and fine bismuth sulfide powder. The possible application of this material in photovoltaic devices is suggested.

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5

Tayebifard, S. A., K. Ahmadi, R. Yazdani-Rad, and M. Doroudian. "New X-ray powder diffraction data for Mo2.85Al1.91Si4.81." Powder Diffraction 21, no. 3 (September 2006): 238–40. http://dx.doi.org/10.1154/1.2244544.

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X-ray powder diffraction data for Mo2.85Al1.91Si4.81 are reported. The new Mo2.85Al1.91Si4.81 compound was successfully prepared using the self-propagating high-temperature synthesis (SHS) technique. The starting atomic mixture of reactant powders was Mo+2(1−x)Si+2xAl with x=0.3. The final powder compound obtained by the SHS technique was determined to be Mo2.85Al1.91Si4.81 by ICP-AES. X-ray powder diffraction pattern of Mo2.85Al1.91Si4.81 was recorded using an X-ray powder diffractometer, Cu Kα radiation, and analyzed by automatic indexing programs. Mo2.85Al1.91Si4.81 was found to be hexagonal with a=4.6929(2) Å and c=6.5515(4) Å. The XRD results are in good agreement with those of Mo2.85Ga2Si4.15.

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6

Li, Degui, Ming Qin, Liuqing Liang, Zhao Lu, Shuhui Liu, Caimin Huang, Bing He, and Lingmin Zeng. "The X-ray powder diffraction data for CeCo3Ni2." Powder Diffraction 29, no. 3 (May 28, 2014): 298–99. http://dx.doi.org/10.1017/s0885715614000463.

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The CeCo3Ni2 compound was synthesized by arc melting under argon atmosphere. High-quality powder X-ray diffraction (XRD) data of CeCo3Ni2 have been collected using a Rigaku SmartLab X-ray powder diffractometer. The refinement of the XRD pattern for the CeCo3Ni2 compound shows that the CeCo3Ni2 is a hexagonal structure, space group P6/mmm (No.191) with a = b = 4.9081(2) Å, c = 4.0034(2) Å, V = 83.52 Å3, Z = 1, and ρx = 8.6347 g cm−3. The Smith–Snyder FOM F30 = 112.7(0.0089, 30) and the intensity ratio RIR = 0.48.

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7

Yamanoi, Toyoko, and Hiromoto Nakazawa. "Parallel-beam X-ray diffractometry using X-ray guide tubes." Journal of Applied Crystallography 33, no. 2 (April 1, 2000): 389–91. http://dx.doi.org/10.1107/s0021889899015344.

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A parallel-beam X-ray diffraction geometry using X-ray guide tubes is proposed to eliminate preferred-orientation effects in powder X-ray diffraction (XRD) patterns and for new applications of XRD. A bundle of X-ray guide tubes (polycapillaries) is used to provide an intense quasi-parallel (approximately 0.2° divergence) and large-diameter (approximately 20 mm) beam of X-rays needed for parallel-beam diffractometry. Mica and silicon particles were agitated inside a cylindrical chamber by a steady flow of N2gas so that they were randomly oriented. The quasi-parallel incident X-ray beam passed through the cloud of floating particles. The diffracted X-rays were detected using a standard 2θ diffractometer. The integrated intensities observed agree well with those calculated from the known model of the crystal structure. This result demonstrates that this type of diffractometry is capable of avoiding preferred-orientation effects and of collecting XRD data for moving powder samples.

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8

Alizadeh, M., K. Ahmadi, and A. Maghsoudipour. "Powder diffraction data for new bismuth yttrium ytterbium oxides by XRD." Powder Diffraction 24, no. 1 (March 2009): 53–55. http://dx.doi.org/10.1154/1.3076129.

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X-ray powder diffraction data for three new bismuth yttrium ytterbium oxide compounds synthesized by solid-state reaction method are reported. The unit-cell dimensions were determined from X-ray diffraction method using Cu Kα radiation and evaluated by indexing programs. The cubic δ-Bi2O3 phase was identified to be the sole crystalline phase in Bi0.82Y0.09Yb0.09O1.5, Bi0.82Y0.12Yb0.06O1.5, and Bi0.82Y0.06Yb0.12O1.5 with lattice constants of a=5.5110(3), 5.5154(2), and 5.5113(2) Å, respectively.

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9

He, Bob. "Algorithms for Two-dimensional XRD Data Evaluation." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1130. http://dx.doi.org/10.1107/s205327331408869x.

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The diffracted x-rays from a polycrystalline (powder) sample form a series diffraction cones in space since large numbers of crystals oriented randomly in the space are covered by the incident x-ray beam. Each diffraction cone corresponds to the diffraction from the same family of crystalline planes in all the participating grains. When a two-dimensional (2D) detector is used for x-ray powder diffraction, the diffraction cones are intercepted by the 2D detector and the x-ray intensity distribution on the sensing area is converted to an image-like diffraction pattern. The 2D pattern contains the scattering intensity distribution as a function of two orthogonal angles. One is the Bragg angle 2θ and the other is the azimuthal angle about the incident x-ray beam, denoted by γ. A 2D diffraction pattern can be analyzed directly or by data reduction to the intensity distribution along γ or 2θ. The γ-integration can reduce the 2D pattern into a diffraction profile analogs to the conventional diffraction pattern which is the diffraction intensity distribution as a function of 2θ angles. This kind of diffraction pattern can be evaluated by most exiting software and algorithms for conventional applications, such as, phase identification, structure refinement and 2θ-profile analysis. However, the materials structure information associated to the intensity distribution along γ direction is lost through γ-integration. The intensity distribution and 2θ variations along γ contain more information, such as the orientation distribution, strain states, crystallite size and shape distribution. In order to understand and analyze 2D diffraction data, new approaches and algorithms are necessary. The diffraction vector approach has been approved to be the genuine theory in 2D data analysis. The unit diffraction vector used for 2D analysis is a function of both 2θ and γ. The unit diffraction vector for all the pixels in the 2D pattern measured in the laboratory coordinates can be transformed to the sample coordinates. The vector components can then be used to derive fundamental equations for many applications, including stress, texture, crystal orientation and crystal size evaluation by γ-profile analysis. The unit diffraction vector is also used in polarization and absorption correction.

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10

Bish, David. "The First X-ray Powder Diffraction Measurements on Mars." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C4. http://dx.doi.org/10.1107/s2053273314099951.

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The CheMin instrument on the Curiosity rover measures XRD and XRF data using Co radiation in transmission geometry. It has analyzed <150 μm portions of eolian soil (Rocknest) and two drill-hole powders (John Klein and Cumberland) from a mudstone [1, 2, Figure 1]. XRD data for Rocknest soil revealed plagioclase, forsteritic olivine, augite, and pigeonite. John Klein and Cumberland are similar, with much less Fe-forsterite and more magnetite than Rocknest. Data were analyzed via Rietveld methods (Topas), and profiles were modeled using beryl-quartz data measured on Mars. CheMin's broad profiles limited analysis of minor phases (<3 wt. %), although the presence of minor phases was evaluated individually for every sample by including each in the Rietveld model and evaluating their effect on the fit. We found no evidence for any perchlorate, carbonate, or sulfate mineral (apart from anhydrite, and bassanite in the mudstones). No phyllosilicate was detected in the soil, but mudstone samples contained two different phyllosilicates, likely trioctahedral smectites. The John Klein XRD pattern had a broad ~10Å peak, whereas Cumberland showed broad peaks at ~13.2Å and ~10Å. The background in all XRD patterns suggested the presence of amorphous/poorly ordered components, which were analyzed using FULLPAT, giving ~27% amorphous content in Rocknest and ~20% in the mudstones. This mineralogy is very similar to that found in soils on the flanks of Mauna Kea volcano, Hawaii. Mineralogy differences between the Rocknest material and the mudstones may be explained by alteration of Fe-forsterite to smectite + magnetite. Combining these results with compositional estimates from unit-cell parameters and bulk chemistry will allow determinations of individual phase compositions, including that of the amorphous component(s). The exact nature of the amorphous component is unclear, but other data show that it is hydrous.

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11

Hansford, G. M. "Phase-targeted X-ray diffraction." Journal of Applied Crystallography 49, no. 5 (September 1, 2016): 1561–71. http://dx.doi.org/10.1107/s1600576716011936.

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A powder X-ray diffraction (XRD) method to enhance the signal of a specific crystalline phase within a mixture is presented for the first time. Specificity to the targeted phase relies on finding coincidences in the ratios of crystal d spacings and the ratios of elemental characteristic X-ray energies. Such coincidences can be exploited so that the two crystal planes diffract through the same scattering angle at two different X-ray energies. An energy-resolving detector placed at the appropriate scattering angle will detect a significantly enhanced signal at these energies if the target mineral or phase is present in the sample. When implemented using high scattering angles, for example 2θ > 150°, the method is tolerant to sample morphology and distance on the scale of ∼2 mm. The principle of the method is demonstrated experimentally using Pd Lα1 and Pd Lβ1 emission lines to enhance the diffraction signal of quartz. Both a pure quartz powder pellet and an unprepared mudstone rock specimen are used to test and develop the phase-targeted method. The technique is further demonstrated in the sensitive detection of retained austenite in steel samples using a combination of In Lβ1 and Ti Kβ emission lines. For both these examples it is also shown how the use of an attenuating foil, with an absorption edge close to and above the higher-energy characteristic X-ray line, can serve to isolate to some degree the coincidence signals from other fluorescence and diffraction peaks in the detected spectrum. The phase-targeted XRD technique is suitable for implementation using low-cost off-the-shelf components in a handheld or in-line instrument format.

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12

Brückner, Sergio. "PULWIN: A program for analyzing powder X-ray diffraction patterns." Powder Diffraction 15, no. 4 (December 2000): 218–19. http://dx.doi.org/10.1017/s0885715600011118.

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A computer program is presented that allows for the analysis of powder X-ray diffraction (XRD) patterns. Some peculiar features of the program are: the aptitude for dealing with diffractograms obtained from semicrystalline polymer samples and the ability to evaluate XRD patterns collected with CPS 120 detectors. The program is available as freeware via anonymous ftp at: ftp.cc.uniud.it under the directory/pulwin/.

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13

Sornadurai, D., B. Panigrahi, V. S. Sastry, and Ramani. "Crystal structure and X-ray powder diffraction pattern of Ti2ZrAl." Powder Diffraction 15, no. 3 (September 2000): 189–90. http://dx.doi.org/10.1017/s0885715600011052.

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We report precision X-ray powder-diffraction (XRD) data of single phase pure Ti2ZrAl. Ti2ZrAl samples were prepared by an arc melting method and annealed at 1000 °C for 30 days. XRD analysis was carried out on these samples and it was found that Ti2ZrAl has a DO19 structure (space group P63/mmc, No. 194). The lattice parameters are found to be a=5.961±0.001 Å and c=4.793±0.001 Å.

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14

Omar, Halo Dalshad. "The Analysis of Copper-Iron Metallic Mixture by Means of XRD and XRF." International Letters of Chemistry, Physics and Astronomy 64 (February 2016): 130–34. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.64.130.

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The objective of the paper has been given on observations based on studies of the three samples of copper-iron (Cu-Fe) alloy have been prepared from 3gm mass of copper of 99.9 % purity powder and adding 1gm weight of iron powder and adding 1.5gm weight of iron powder. A discussion about simple and low cost preparation of Cu-Fe alloy by Mini Mill 2 Panalytical and preparation of the sample was rotating at 10 min and in case of grinding samples at high speed 300 rpm. Herzog press Panalytical used to produce pressed powder Cu-Fe alloy. The characters of Cu-Fe particles are depending on their size, shape and chemical surroundings. X-Ray Diffraction (XRD) (Model: Panalytical Empyrean) study is most important tool used in powder materials science. For studied three samples the value of (111) plane has the highest value compared to other planes. The spectra obtained were analyzed using X-ray fluorescence (XRF) (Model: Rigaku-NEX CG). From the spectra obtained, there were some elements to be present in the sample were Cu-Fe. The intensity of Cu pure is larger than impurity copper samples analysis by XRD and XRF. Also impurity affects the intensity, (2θ) position and shape of the X-ray spectra.

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15

Martí-Rujas, Javier. "Structural elucidation of microcrystalline MOFs from powder X-ray diffraction." Dalton Transactions 49, no. 40 (2020): 13897–916. http://dx.doi.org/10.1039/d0dt02802a.

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16

Ellouze, M., W. Boujelben, and H. Fuess. "Rietveld refinement X-ray powder data of Pr0.7Ba0.3MnO3." Powder Diffraction 18, no. 1 (March 2003): 29–31. http://dx.doi.org/10.1154/1.1515296.

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Powder X-ray diffraction (XRD) data were collected for Pr0.7Ba0.3MnO3. This sample was prepared using the conventional solid state reaction by mixing Pr6O11, Mn2O3, and BaCO3 up to 99.9% purity at 1400 °C in air for 60 h. XRD analysis using the Rietveld method was carried out and it was found that this manganite sample has orthorhombic symmetry with Pnma space group. The lattice parameters are found to be a=5.4900 Å, b=7.7578 Å, and c=5.5227 Å.

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17

Wang, H., M. J. Kirkham, T. R. Watkins, E. A. Payzant, J. R. Salvador, A. J. Thompson, J. Sharp, D. Brown, and D. Miller. "Neutron and X-ray powder diffraction study of skutterudite thermoelectrics." Powder Diffraction 31, no. 1 (February 17, 2016): 16–22. http://dx.doi.org/10.1017/s0885715615000937.

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N- and p-type filled-skutterudite materials prepared for thermoelectric power generation modules were analyzed by neutron diffraction at the POWGEN beam line of the Spallation Neutron Source (SNS) and X-ray diffraction (XRD). The skutterudite powders were processed by melt spinning, followed by ball milling and annealing. The n-type material consists of Ba–Yb–Co–Sb and the p-type material consists of Di–Fe–Ni–Sb or Di–Fe–Co–Sb (Di = didymium, an alloy of Pr and Nd). Powders for prototype module fabrication from General Motors and Marlow Industries were analyzed in this study. XRD and neutron diffraction studies confirm that both the n- and p-type materials have cubic symmetry. Structural Rietveld refinements determined the lattice parameters and atomic parameters of the framework and filler atoms. The cage filling fraction was found to depend linearly on the lattice parameter, which in turn depends on the average framework atom size. This knowledge may allow the filling fraction of these skutterudite materials to be purposefully adjusted, thereby tuning the thermoelectric properties.

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18

Riello, Pietro, Andrea Lausi, Jennifer Macleod, Jasper Rikkert Plaisier, Giulio Zerauschek, and Paolo Fornasiero. "In situreaction furnace for real-time XRD studies." Journal of Synchrotron Radiation 20, no. 1 (November 10, 2012): 194–96. http://dx.doi.org/10.1107/s0909049512039246.

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The new furnace at the Materials Characterization by X-ray Diffraction beamline at Elettra has been designed for powder diffraction measurements at high temperature (up to 1373 K at the present state). Around the measurement region the geometry of the radiative heating element assures a negligible temperature gradient along the capillary and can accommodate either powder samples in capillary or small flat samples. A double capillary holder allows flow-through of gas in the inner sample capillary while the outer one serves as the reaction chamber. The furnace is coupled to a translating curved imaging-plate detector, allowing the collection of diffraction patterns up to 2θ ≃ 130°.

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19

Boulc'h, Florence, Marie-Claude Schouler, Patricia Donnadieu, Jean-Marc Chaix, and Elisabeth Djurado. "DOMAIN SIZE DISTRIBUTION OF Y-TZP NANO-PARTICLES USING XRD AND HRTEM." Image Analysis & Stereology 20, no. 3 (May 3, 2011): 157. http://dx.doi.org/10.5566/ias.v20.p157-161.

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Yttria doped nanocrystalline zirconia powder was prepared by spray-pyrolysis technique. Powder crystallized into tetragonal form, as dense and compositionally homogeneous polycrystalline spheres. X-Ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) have been used in order to characterize the mean size and the size distribution of crystalline domains. An average size of 6 nm was calculated by Scherrer formula from X-Ray diffraction pattern. The domain size, determined by analysis method developed by Hytch from HRTEM observations, ranges from 5 to 22 nm with a main population around the value 12 nm. Limits and complementary nature of XRD and HRTEM methods are discussed.

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20

Achary, S. N., G. D. Mukherjee, A. K. Tyagi, and B. K. Godwal. "Powder X-ray diffraction data of a new polymorph of HfMo2O8." Powder Diffraction 18, no. 2 (June 2003): 147–49. http://dx.doi.org/10.1154/1.1536195.

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A new polymorph of HfMo2O8 (β-form) is synthesized under high pressure and high temperature conditions. The powder X-ray diffraction (XRD) data could be explained based on a monoclinic lattice (Space Group: C2/c No. 15) with the unit cell parameters as: a=11.415(3), b=7.906(2), c=7.438(2) Å and β=122.37(2)°, V=566.9(2) Å3. The detailed powder XRD data and analysis are reported herein.

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21

Harris, Kenneth. "Structure Determination of Molecular Solids from Powder X-ray Diffraction Data." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1557. http://dx.doi.org/10.1107/s2053273314084423.

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Structure determination of organic molecular solids from powder X-ray diffraction (XRD) data [1] is nowadays carried out extensively by researchers in both academia and industry, and the development of new methodology in this field has made particularly significant impact in the pharmaceuticals industry within the last 20 years or so. However, although software for carrying out each stage of the procedure for structure determination from powder XRD data is now readily accessible and relatively straightforward to use, it is essential that the results from such structure determination calculations are subjected to careful scrutiny to confirm that the final structure obtained is actually correct. In this regard, it can be particularly advantageous to augment the analysis of the powder XRD data and to assist the scrutiny of the structural results by considering complementary structural information derived from other experimental and computational techniques. Techniques that can be particularly valuable in this regard include solid-state NMR spectroscopy, energy calculations (either on individual molecules or periodic crystal structures), vibrational spectroscopies, and techniques of thermal analysis (e.g. DSC and TGA). The lecture will give an overview of the current "state of the art" in the structure determination of organic materials from powder XRD data, giving emphasis [2,3] to the opportunities to enhance the structure determination process by making use of information derived from other experimental (especially solid-state NMR) and computational techniques. Recent results will be presented, with emphasis on raising issues of relevance to research on pharmaceutical materials.

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22

Siqueira, Guilherme Oliveira, Érica Gonçalves Gravina, Jackson Antônio Lamounier Camargos Resende, and Nelson Gonçalves Fernandes. "XRD diffraction data and Rietveld refinement of Na8[Si6Al6O24]Cl2." Powder Diffraction 24, no. 1 (March 2009): 41–43. http://dx.doi.org/10.1154/1.3078423.

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A natural sodalite from the geological site Alkaline Complex of Floresta Azul, Bahia, Brazil, has been characterized by electron microprobe, infrared spectroscopy, and powder high-resolution X-ray diffraction techniques. The mineral is an aluminosilicate framework, formed by cages called sodalite unity. Although the sample is natural, the chemical analysis reveals that it is indeed the end member sodalite sensu strictu, Na8[Si6Al6O24]Cl2. Infrared spectroscopy shows Si, Al tetrahedral-oxygen stretching nonsymmetric mode, stretching symmetric mode, and bending modes. Indexing of the experimental X-ray diffraction pattern led to cubic space group P-43n, and unit-cell parameters: a=8.8767(7) Å, Dx=2.301 g cm−3, and V=699.46(1) Å3. X-ray diffraction data are reported. Rietveld refinement was also performed, and the confidence factors are Rp=0.079, Rwp=0.118, and χ2=2.19. The structure of the minerals of sodalite group holds four different tetrahedra: AlO4, ClNa4, Na(ClO3), and SiO4, with Al, Cl, Na, and Si located at the center of each tetrahedron.

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23

Lin, Wen Song, C. H. Wen, and Liang He. "Magnetic Properties of Bulk Zn_0.95-XMn_XFe_0.05O₂ Prepared by Sol-Gel Method and Subsequent Hot Pressing." Advanced Materials Research 268-270 (July 2011): 356–59. http://dx.doi.org/10.4028/www.scientific.net/amr.268-270.356.

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Mn, Fe doped ZnO powders (Zn0.95-xMnxFe0.05O2, x≤0.05) were synthesized by an ameliorated sol-gel method, using Zn(CH3COO)2, Mn(CH3COO)2and FeCl2as the raw materials, with the addition of vitamin C as a kind of chemical reducer. The resulting powder was subsequently compacted under pressure of 10 MPa at the temperature of 873K in vacuum. The crystal structure and magnetic properties of Zn0.95-xMnxFe0.05O2powder and bulk samples have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of manganese, iron and zinc in the samples. The x-ray diffraction (XRD) results showed that Zn0.95-xMnxFe0.05O (x≤0.05) samples were single phase with the ZnO-like wurtzite structure. No secondary phase was found in the XRD spectrum. X-ray photoelectron spectroscopy (XPS) showed that Fe and Mn existed in Zn0.95-xMnxFe0.05O2samples in Fe2+and Mn2+states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Mn, Fe co-doped ZnO samples.

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24

Zhang, Hua Yong, Yong Mei Xia, Xiao Jian Liu, and Tian Duo Li. "Research on Influence of Diffractometer Slits on XRD Pattern." Key Engineering Materials 544 (March 2013): 441–44. http://dx.doi.org/10.4028/www.scientific.net/kem.544.441.

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X-ray diffraction analysis is a convenient and important route to investigate crystalline materials. With powder materials, calcium carbonate as target, the effects of scatter slit, soller slit and receiving slit of Bruker D8 ADVANCE diffractometer on the diffraction pattern based on information, such as the background intensity, peak height, intensity and full width at half maximum, which provide the evidence for slits selection.

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25

Tas, A. Cüneyt. "X-ray diffraction data for flux-grown calcium hydroxyapatite whiskers." Powder Diffraction 16, no. 2 (June 2001): 102–6. http://dx.doi.org/10.1154/1.1330273.

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Calcium hydroxyapatite (Ca10(PO4)6(OH)2) whiskers were prepared by using the technique of molten salt synthesis with the fluxing agent of potassium sulphate (K2SO4). A tentative x-ray diffraction (XRD) pattern was suggested for the produced whiskers. Phase purity, composition, and morphology of the whiskers were investigated by powder XRD, inductively coupled plasma-atomic emission spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy, respectively.

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Hubbard, Camden R., and Robert L. Snyder. "RIR - Measurement and Use in Quantitative XRD." Powder Diffraction 3, no. 2 (June 1988): 74–77. http://dx.doi.org/10.1017/s0885715600013257.

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AbstractThe Reference Intensity Ratio (RIR) is a general, instrument-independent constant for use in quantitative phase analysis by the X-ray powder diffraction internal standard method. When the reference standard is corundum, RIR is known as I/Ic; These constants are collected in the Powder Diffraction File (1987), can be calculated, and can be measured. Recommended methods for accurate measurement of RIR constants are presented, and methods of using these constants for quantitative analysis are discussed. The numerous, complex constants in Copeland and Bragg's method introduced to account for superimposed lines can be simply expressed in terms of RIR constants and relative intensities. This formalism also permits introduction of constraints and supplemental equations based on elemental analysis.

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Jin, Zong-ming, Ya-jie Chen, and Zheng Jin. "X-ray powder diffraction analysis of NiZnCuSn ferrite containing antimony." Powder Diffraction 10, no. 2 (June 1995): 120–21. http://dx.doi.org/10.1017/s0885715600014482.

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Crystallographic data for Ni0.41Zn0.60Cu0.01Fe2.04−xSbxO4+δ (0.01≤x≤0.12) ferrites are significantly influenced by small additions of antimony. XRD analysis reveals that changes in crystal data for small Sb substitutions differ markedly from those for greater Sb substitutions. The differences are due to the contribution of the Sb ion. Complete crystal data for six solid solution compositions are reported. An X-ray powder diffraction pattern for Ni0.41Zn0.60Cu0.02Sn0.01Fe2.02Sb0.02O4+δ is given.

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Huang, Jirong, Lingmin Zeng, and Zhihui Sun. "X-ray powder diffraction data and Rietveld refinement of CrFe3NiSn5." Powder Diffraction 19, no. 4 (December 2004): 372–74. http://dx.doi.org/10.1154/1.1763153.

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X-ray power diffraction data for CrFe3NiSn5 are reported. Indexing the XRD power pattern and Rietveld refinement shows that the compound crystallizes in the hexagonal crystal system, space group P6mm (No. 183) with lattice parameters a=5.3168(1) Å, c=4.4261(1) Å, z=0.6 and Dcalc=8.011 g cm−3. The crystal structure of CrFe3NiSn5 is of the CoSn structure type with Fe, Cr and Ni disordered in the Co position.

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Yeo, W. S., Z. Nur Amirah, H. S. C. Metselaar, and T. H. Ong. "X-Ray Powder Diffraction Studies of Mechanically Milled Cobalt." Advanced Materials Research 626 (December 2012): 913–17. http://dx.doi.org/10.4028/www.scientific.net/amr.626.913.

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The allotropic phase transformation of cobalt powder prepared by high-energy ball milling was investigated as a function of milling time. Measurement of crystallite size and micro-strain in the powder systems milled for different times were conducted by X-ray diffractometry. The X-ray diffraction (XRD) peaks were analyzed using the Pearson VII profile function in conjunction with Rietveld method. X-ray diffraction line broadening revealed that allotropic transformation between face-centred-cubic phase (fcc) and hexagonal close-packed phase (hcp) in cobalt is grain size dependent and also on the accumulation of structure defects. The results showed that the phase formation of cobalt depends on the mill intensity that influences of both the grain size and the accumulation of structure defects. However, this theory alone is not adequate to explain the effects in this work. It was found that the total surface energy (Ω) theory satisfactorily explains the phase transformation behavior of cobalt. The smaller value of surface energy (Ω) of the fcc crystal than the hcp phase when size decreases may alter the qualitative aspects of the phase formation.

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30

Yan, Xue, Z. Hua, J. Liu, Bin Li, and X. Cheng. "Crystal Structure and Thermal Expansion of Ge-Doped Mn₃CuN." Advanced Materials Research 412 (November 2011): 422–26. http://dx.doi.org/10.4028/www.scientific.net/amr.412.422.

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The Ge doped Mn3CuN powder was synthesized using gas-solid reaction method with manganese, copper, germanium powders and N2 gas as raw material. The phase constitute of the as-prepared powder was characterized using X-ray diffraction (XRD). The intrinsic and macro thermal expansion coefficients of the powder were measured by in-situ X-ray diffraction at different temperatures and TMA, respectively. The crystal structure of the powders was analyzed using Rietveld refinement method. The results show that the pure Mn3(Cu0.5Ge0.5)N powder can be prepared via the gas-solid method at 850 °C. The crystal structures of Mn3(Cu0.5Ge0.5)N and Mn3CuN both have the antiperovskite structures. The intrinsic and macro thermal expansion coefficient of Mn3(Cu0.5Ge0.5)N powder is-16.8×10-6K-1 and-17×10-6K-1, respectively. The temperature range with negative thermal expansion is from-80 °C to 50 °C.

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31

Vamvakeros, Antonios, Simon D. M. Jacques, Marco Di Michiel, Vesna Middelkoop, Christopher K. Egan, Robert J. Cernik, and Andrew M. Beale. "Removing multiple outliers and single-crystal artefacts from X-ray diffraction computed tomography data." Journal of Applied Crystallography 48, no. 6 (November 28, 2015): 1943–55. http://dx.doi.org/10.1107/s1600576715020701.

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This paper reports a simple but effective filtering approach to deal with single-crystal artefacts in X-ray diffraction computed tomography (XRD-CT). In XRD-CT, large crystallites can produce spots on top of the powder diffraction rings, which, after azimuthal integration and tomographic reconstruction, lead to line/streak artefacts in the tomograms. In the simple approach presented here, the polar transform is taken of collected two-dimensional diffraction patterns followed by directional median/mean filtering prior to integration. Reconstruction of one-dimensional diffraction projection data sets treated in such a way leads to a very significant improvement in reconstructed image quality for systems that exhibit powder spottiness arising from large crystallites. This approach is not computationally heavy which is an important consideration with big data sets such as is the case with XRD-CT. The method should have application to two-dimensional X-ray diffraction data in general where such spottiness arises.

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32

Etschmann, Barbara, and Nobuo Ishizawa. "A synchrotron X-ray diffraction study of a small congruent LiNbO3 crystal: A compatible approach to powder diffraction." Powder Diffraction 16, no. 2 (June 2001): 81–85. http://dx.doi.org/10.1154/1.1365124.

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Single-crystal synchrotron X-ray diffraction (XRD) data were collected and refined for congruent lithium niobate crystals 8 and 6 μm in diameter, sizes that are comparable to the size of the powder particles used in powder diffraction. The motivation for using such small crystals is to minimize problems such as extinction, which decrease with crystal size. The R/wR factors were 0.011/0.014 and 0.019/0.018, for the 8 and 6 μm data, respectively, and the goodness of fit factors were 2.3(1) and 1.63(8), which compare favorably with values obtained from previous powder and single-crystal diffraction studies. Results from single-crystal XRD using crystals less than 10 μm in size may rival those obtained from powder diffraction.

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33

Georgieva, Irena, Ivan Ivanov, and Ognyan Petrov. "X-ray powder diffraction data for Ba3MnSi2O8—A new phase in the system BaO–MnO–SiO2." Powder Diffraction 11, no. 1 (March 1996): 26–27. http://dx.doi.org/10.1017/s088571560000885x.

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A new compound—Ba3MnSi2O8 in the system BaO–MnO–SiO2 was synthesized and studied by powder X-ray diffraction. The compound is hexagonal, space group—P6/mmm, a=5.67077 Å, c=7.30529 Å, Z=1, Dx=5.353. The obtained powder X-ray diffractometry (XRD) data were interpreted by the Powder Data Interpretation Package.

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Schuetzke, Jan, Alexander Benedix, Ralf Mikut, and Markus Reischl. "Enhancing deep-learning training for phase identification in powder X-ray diffractograms." IUCrJ 8, no. 3 (April 1, 2021): 408–20. http://dx.doi.org/10.1107/s2052252521002402.

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Within the domain of analyzing powder X-ray diffraction (XRD) scans, manual examination of the recorded data is still the most popular method, but it requires some expertise and is time consuming. The usual workflow for the phase-identification task involves software for searching databases of known compounds and matching lists of d spacings and related intensities to the measured data. Most automated approaches apply some iterative procedure for the search/match process but fail to be generally reliable yet without the manual validation step of an expert. Recent advances in the field of machine and deep learning have led to the development of algorithms for use with diffraction patterns and are producing promising results in some applications. A limitation, however, is that thousands of training samples are required for the model to achieve a reliable performance and not enough measured samples are available. Accordingly, a framework for the efficient generation of thousands of synthetic XRD scans is presented which considers typical effects in realistic measurements and thus simulates realistic patterns for the training of machine- or deep-learning models. The generated data set can be applied to any machine- or deep-learning structure as training data so that the models learn to analyze measured XRD data based on synthetic diffraction patterns. Consequently, we train a convolutional neural network with the simulated diffraction patterns for application with iron ores or cements compounds and prove robustness against varying unit-cell parameters, preferred orientation and crystallite size in synthetic, as well as measured, XRD scans.

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35

Bish, D. L., and Steve J. Chipera. "Accuracy in Quantitative X-ray Powder Diffraction Analyses." Advances in X-ray Analysis 38 (1994): 47–57. http://dx.doi.org/10.1154/s0376030800017638.

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Abstract Accuracy, or how well a measurement conforms to the true value of a parameter, is important in XRD analyses in three primary areas, 1) 26 position or d-spacing; 2) peak shape; and 3) intensity. Instrumental factors affecting accuracy include zero-point, axial-divergence, and specimen- displacement errors, step size, and even uncertainty in X-ray wavelength values. Sample factors affecting accuracy include specimen transparency, structural strain, crystallite size, and preferred orientation effects. In addition, a variety of other sample-related factors influence the accuracy of quantitative analyses, including variations in sample composition and order/disorder. The conventional method of assessing accuracy during experimental diffractometry measurements is through the use of certified internal standards. However, it is possible to obtain highly accurate d-spacings without an internal standard using a well-aligned powder diffractometer coupled with data analysis routines that allow analysis of and correction for important systematic errors. The first consideration in such measurements is the use of methods yielding precise peak positions, such as profile fitting. High accuracy can be achieved if specimen-displacement, specimen- transparency, axial-divergence, and possibly zero-point corrections are included in data analysis. It is also important to consider that most common X-ray wavelengths (other than Cu Kα1) have not been measured with high accuracy. Accuracy in peak-shape measurements is important in the separation of instrumental and sample contributions to profile shape, e.g., in crystallite size and strain measurements. The instrumental contribution must be determined accurately using a standard material free from significant sample-related effects, such as NIST SRM 660 (LaB6). Although full-pattern fitting methods for quantitative analysis are available, the presence of numerous systematic errors makes the use of an internal standard, such as a-alumina mandatory to ensure accuracy; accuracy is always suspect when using external-standard, constrained-total quantitative analysis methods. One of the most significant problems in quantitative analysis remains the choice of representative standards. Variations in sample chemistry, order-disorder, and preferred orientation can be accommodated only with a thorough understanding of the coupled effects of all three on intensities. It is important to recognize that sample preparation methods that optimize accuracy for one type of measurement may not be appropriate for another. For example, the very fine crystallite size that is optimum for quantitative analysis is unnecessary and can even be detrimental in d-spacing and peak shape measurements.

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36

dalla Valentina, Luiz Oliveira Veriano, Marilena Valadares Folgueras, Wanessa Rejane Knop, Maria Cristina Pacheco do Nascimento, and Glaucia Aparecida Prates. "Quality Characterization of Iron Dust Exhaust Thermal as Alternative Ceramic Coating Raw Materials in a Brazilian Company." Advanced Materials Research 1077 (December 2014): 135–38. http://dx.doi.org/10.4028/www.scientific.net/amr.1077.135.

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As the raw materials used in the ceramic materials manufacturing are natural, it is important to use them as a alternative materials, thus decreasing the elements demand taken from nature. This paper aims the characterization of foundry solid powder exhaust from a brazilian company located in Joinville - SC as an alternative raw material for ceramic coating by X-ray diffraction (XRD), thermal analysis (DSC) and thermogravimetric (TG). The dust depletion is caused in the manufacturing mold sand process, when the bentonita (clay), silica sand and coal during the metal parts production are mixed in green sand production. The raw materials were characterized through X-ray diffraction (XRD), thermal (DSC) and thermogravimetric analisys (TG). The atomized powder thermogravimetric analysis curve shows three intervals associated with the mass loss and it is typical of clay commercial application.

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37

Zeng, Chao, Guoqiang Lin, Weijing Zeng, and Wei He. "Crystal structure and powder X-ray diffraction data for new Tb3CuAl3Ge2 compound." Powder Diffraction 30, no. 1 (February 20, 2015): 63–66. http://dx.doi.org/10.1017/s0885715614000955.

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The crystal structure of new Tb3CuAl3Ge2 quaternary compound was studied by the Rietveld method from powder X-ray diffraction (XRD) data. The Tb3CuAl3Ge2 compound crystallized in the hexagonal Y3NiAl3Ge2-type structure with space group P-62m (no. 189) and lattice parameters a = 7.0041(2) Å, c = 4.1775(1) Å, V = 177.48 Å3. There is only one formula in each unit cell, Z = 1, and the density of Tb3CuAl3Ge2 is ρx = 7.1696 g cm−3. The reliability factors characterizing the Rietveld refinement results are Rp = 6.43%, Rwp = 8.65%, RB = 4.81%, and RF = 4.09%, respectively. The powder XRD data of Tb3CuAl3Ge2 were presented and the reliability of indexation is F30 = 120.9(0.0073, 34).

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38

Yang, Lin Lin, Yong Gang Wang, Xiao Feng Wang, Yu Jiang Wang, and Gao Rong Han. "Hydrothermal Synthesis and Characterization of PbTiO₃ Microrods." Advanced Materials Research 148-149 (October 2010): 903–6. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.903.

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PbTiO3 microrods were successfully synthesized via a surfactants-free hydrothermal method. The powders were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and photoluminescent spectra techniques (PL). It was found that the precursor played a key role in the formation of PbTiO3 microrods.

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39

Pu, Yong Ping, Ning Xu, and Xiao Long Chen. "A Novel Method for Quantitative Analysis of Tetragonal Phase in Barium Titanate Powders by X-Ray Diffraction." Advanced Materials Research 156-157 (October 2010): 1006–9. http://dx.doi.org/10.4028/www.scientific.net/amr.156-157.1006.

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Quantitative analysis of tetragonal phase in barium titanate powders and fundament of standard curve was discussed from the result of X-ray diffraction (XRD) experiment via testing the standard series prepared powder samples. Some different conclusions compared with the past researches were drawn by analyzing the XRD data including the integrated intensity of a certain diffraction peak, difference in 2θ between peak (002) and (200) △2θ and d (interplanar spacing) value. Thus a useful method was provided for quantitative analysis tetragonal phase in barium titanate powders by synthesized by hydrothermal method.

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40

Valério, Adriana, Sérgio L. Morelhão, Alex J. Freitas Cabral, Márcio M. Soares, and Cláudio M. R. Remédios. "X-Ray Dynamical Diffraction in Powder Samples with Time-Dependent Particle Size Distributions." MRS Advances 5, no. 29-30 (December 2, 2019): 1585–91. http://dx.doi.org/10.1557/adv.2019.445.

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ABSTRACTIn situ X-ray diffraction is one of the most useful tools for studying a variety of processes, among which crystallization of nanoparticles where phase purity and size control are desired. Growth kinetics of a single phase can be completely resolved by proper analysis of the diffraction peaks as a function of time. The peak width provides a parameter for monitoring the time evolution of the particle size distribution (PSD), while the peak area (integrated intensity) is directly related to the whole diffracting volume of crystallized material in the sample. However, to precisely describe the growth kinetics in terms of nucleation and coarsening, the correlation between PSD parameters and diffraction peak widths has to be established in each particular study. Corrections in integrated intensity values for physical phenomena such as variation in atomic thermal vibrations and dynamical diffraction effects have also to be considered in certain cases. In this work, a general correlation between PSD median value and diffraction peak width is deduced, and a systematic procedure to resolve time-dependent lognormal PSDs from in situ XRD experiments is described in details. A procedure to correct the integrated intensities for dynamical diffraction effects is proposed. As a practical demonstration, this analytical procedure has been applied to the single-phase crystallization process of bismuth ferrite nanoparticles.

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41

Reid, Joel. "Application of synchrotron powder diffraction to research and issues in mining." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C950. http://dx.doi.org/10.1107/s2053273314090494.

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Powder diffraction (PXRD) is an important tool for synergistic synchrotron studies of mining issues. Quantitative phase analysis with powder diffraction often provides basic information required to guide additional studies such as X-ray absorption (XAS) or micro-diffraction (μ-XRD). Elemental speciation in dilute and complex mineralogical systems with X-ray absorption near edge structure (XANES) spectroscopy is critically dependent on high quality phase pure standards, which are generally appraised using PXRD. This talk will examine the powder diffraction capabilities at the CLS, and discuss application of PXRD to mining issues as part of a combined synchrotron approach using examples.

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42

Orlando, M. T. D., L. Kuplich, D. O. de Souza, H. Belich, J. B. Depianti, C. G. P. Orlando, E. F. Medeiros, et al. "Study of calcium oxalate monohydrate of kidney stones by X-ray diffraction." Powder Diffraction 23, S1 (March 2008): S59—S64. http://dx.doi.org/10.1154/1.2903738.

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X-ray powder diffraction was used to study the phase composition of human renal calculi. The stones were collected from 56 donors in Vitória, Espírito Santo state, southeastern Brazil. An XRD phase quantification revealed that 61% of the studied renal stones were composed exclusively of calcium oxalate [34% formed only by calcium oxalate monohydrate (COM) and 27% presents both monohydrate and dihydratate calcium oxalate]. The 39% multi-composed calculi have various other phases such as uric acid and calcium phosphate. Rietveld refinement of XRD data of one apparent monophasic (COM) renal calculus revealed the presence of a small amount of hydroxyapatite. The presence of this second phase and the morphology of the stone (ellipsoidal) indicated that this calculus can be classified as non-papillary type and its nucleation process developed in closed kidney cavities. In order to show some advantages of the X-ray powder diffraction technique, a study of the phase transformation of monohydrate calcium oxalate into calcium carbonate (CaCO3) was carried out by annealing of a monophasic COM calculi at 200, 300, and 400 °C for 48 h in a N2 gas atmosphere. The results of the XRD for the heat treated samples is in good agreement with the thermogravimetric analysis found in the literature and shows that X-ray powder diffraction can be used as a suitable technique to study the composition and phase diagram of renal calculi.

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43

Koster, Herman, and Fre´de´ric H. B. Mertins. "Powder diffraction of the cubic perovskite Ba0.5Sr0.5Co0.8Fe0.2O3−δ." Powder Diffraction 18, no. 1 (March 2003): 56–59. http://dx.doi.org/10.1154/1.1536927.

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X-ray powder diffraction data for Ba0.5Sr0.5Co0.8Fe0.2O3−δ are reported. The powder was prepared using a metal-EDTA complexing method. The XRD data could be fitted with a primitive cubic unit cell in space group Pm3m (No. 221). The Rietveld refined unit cell parameter is ac=0.398 30(3) nm with Z=1 and Dx=5.75 g/cm3.

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44

Torres-Gomez, Nayely, Alfredo R. Vilchis-Nestor, Rosa Maria Gomez-Espinosa, and Ivan Garcia-Orozco. "Synthesis and Characterization of Copper(II) Complexes with Long Chain Dithiocarbamates." Advanced Materials Research 976 (June 2014): 164–68. http://dx.doi.org/10.4028/www.scientific.net/amr.976.164.

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Copper complexes of dithiocarbamates ligands were obtained from RNH2 (R = C6H13-, C12H25- y C18H37-) and an excess of CS2 in the presence of NaOH. Sodium hexyldithiocarbamate is not possible to isolate from solution but the other two were obtained and characterizedby infrared spectroscopy, UV-vis and powder X-ray diffraction. Copper complexes were obtained in situ from ligand solution as greenish powders. All the complexes were characterized by infrared spectroscopy, UV-vis, powder X-ray diffraction and Scanning Electron Microscopy. The complexes show an amorphous phase in the case of DCu12 and nanocrystalline structure for DCu18, as observed in XRD.

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45

Bell, A. M. T., H.-P. Liermann, J. Bednarcik, and C. M. B. Henderson. "Synchrotron X-ray powder diffraction study on synthetic Sr-Fresnoite." Powder Diffraction 28, S2 (September 2013): S333—S338. http://dx.doi.org/10.1017/s0885715613000936.

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The Sr analogue of the mineral fresnoite (Sr2TiSi2O8) is of interest as a potential storage medium for radioactive Sr from nuclear waste. No high or low temperature crystal structure information is known on this phase. Therefore high-resolution synchrotron X-ray powder diffraction measurements have been done on a synthetic sample of Sr-fresnoite in the temperature range 87-1223K. This was done as a test experiment using the HRPD beamline P02.1 at PETRA-III, DESY. Synchrotron X-ray wavelengths of 0.2067(3)Å (293K and 573-1223K) and 0.2079(3)Å (87-499K) were used. Powder diffraction data were collected with a counting time of 30s using a PerkinElmer XRD 1621 flat panel image plate detector. CeO2 was included as an internal standard to calibrate the sample to detector distance. The P4bm tetragonal crystal structure of fresnoite (Ba2TiSi2O8) was used as a starting model for Sr-fresnoite. Small amounts of SrTiO3 and SrSiO3 were also found as impurities in this sample; therefore four-phase Rietveld refinements were done. The P4bm fresnoite structure is retained over the temperature range 87-1223K.

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46

Chakartnarodom, Parinya, Nuntaporn Kongkajun, and Edward A. Laitila. "Influence of Scanning Parameters on X-Ray Diffraction Peaks of Copper." Key Engineering Materials 751 (August 2017): 202–6. http://dx.doi.org/10.4028/www.scientific.net/kem.751.202.

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The aim of this work is to study the influence of x-ray diffractometer scanning parameters on the integrated intensity and full-width at half maximum (FWHM) of copper powder x-ray diffraction peaks by using statistical analysis methods. X-ray diffraction (XRD) analysis of the copper powder was accomplished using step scan mode with step sizes of 0.03o and 0.05o 2q, and preset time changes from 0.1-3.5 s. Integrated intensity of an x-ray peak was calculated by the numerical method. FWHM was measured as the width of Pearson VII model of the x-ray peak at the half-maximum intensity. The statistical analysis methods including linear regression and statistical hypothesis test were used to analyze the correlation between the preset time and the error on integrated intensity calculation, and the FWHM of a peak on the XRD pattern. The results from statistical analysis show that increasing the preset time from 0.1 s to 3.5 s does not affect the FWHM of an x-ray peak, but it reduces the relative error in integrated intensity calculation. Moreover, using the preset time greater than 1 s will minimize the relative error in integrated intensity calculation of an x-ray peak. While step size did not affect both the relative error in integrated intensity calculation or FWHM, the smaller step size would provide more data points for better accurate model of an x-ray peak.

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47

Endler, Ingolf, Mandy Höhn, Björn Matthey, Jakub Zálešák, Jozef Keckes, and Reinhard Pitonak. "Powder Diffraction Data of Aluminum-Rich FCC-Ti1−xAlxN Prepared by CVD." Coatings 11, no. 6 (June 5, 2021): 683. http://dx.doi.org/10.3390/coatings11060683.

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Fcc-Ti1−xAlxN-based coatings obtained by Physical Vapor Deposition (PVD) or Chemical Vapor Deposition (CVD) are widely used as wear-resistant coatings. However, there exists no JCPDF card of fcc-Ti1−xAlxN for the XRD analysis of such coatings based on experimental data. In this work, an aluminum-rich fcc-Ti1−xAlxN powder was prepared and, for the first time, a powder diffraction file of fcc-Ti1−xAlxN was determined experimentally. In the first step, a 10 µm thick Ti1−xAlxN coating was deposited on steel foil and on cemented carbide inserts by CVD. The steel foil was etched and flakes of a free-standing Ti1−xAlxN layer were obtained of which a part consisted of a pure fcc phase. A powder was produced using the major part of the flakes of the free-standing Ti1−xAlxN layer. Following the Ti1−xAlxN coating, a flake of the free-standing layer and the powder were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction and high-resolution transmission electron microscopy (SAED–HRTEM), wavelength dispersive X-ray spectroscopy (WDS) and energy dispersive X-ray spectroscopy (EDS). The powder consisted of 88% fcc-Ti1−xAlxN. The stoichiometric coefficient of fcc-Ti1−xAlxN was measured on a flake containing only the fcc phase. A value of x = 0.87 was obtained. Based on the powder sample, the XRD data of the pure fcc-Ti1−xAlxN phase were measured and the lattice constant of the fcc-Ti1−xAlxN phase in the powder was determined to be a = 0.407168 nm. Finally, a complete dataset comprising relative XRD intensities and lattice parameters for an fcc-Ti0.13Al0.87N phase was provided.

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48

Taguchi, Takeyoshi. "A new position sensitive area detector for high-speed and high-sensitivity X-ray diffraction analysis." Powder Diffraction 21, no. 2 (June 2006): 97–101. http://dx.doi.org/10.1154/1.2204063.

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A state-of-art semiconductor technology-based position sensitive area detector, namely D/teX-25, has recently been developed for high-speed and high-sensitivity X-ray diffraction (XRD) analysis of materials. X-ray powder diffraction intensities obtained by a D/teX-25 detector were found to over 50 times higher than those by a conventional scintillation counter. A D/teX-25 detector mounted on a conventional 2 kW XRD system has been used to collect ultrafast XRD data with scanning speeds up to 160°2θ per minute. Ultrahigh-speed XRD is particularly useful for time-resolved dynamical and in-situ studies. A D/teX-25 detector was successfully used on a Rigaku XRD differential scanning calorimetry (DSC) system for simultaneous measurements of XRD and DSC data under controlled temperature and humidity conditions. This has made possible the study of complex and rapid phase transformations of pharmaceutical terfenadine. The D/teX-25 area detector has also been used for recording two-dimensional XRD patterns showing the particle-size effects on α-quartz powder intensities and to obtain digital X-ray topographic images of a complex dislocation network in a Si wafer.

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49

Lawton, Stephen L., and Lawrence S. Bartell. "Application of the overlap integral in X-ray diffraction powder pattern recognition." Powder Diffraction 9, no. 2 (June 1994): 124–35. http://dx.doi.org/10.1017/s088571560001410x.

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Use of the overlap integral in X-ray diffraction (XRD) powder pattern recognition of crystalline materials is presented. The mathematical expression, derived specifically for diffraction data, provides a measure of similarity between two patterns. Each pattern is represented by a normalized mathematical function. The index of similarity, or overlap integral, indicates how faithfully the two functions overlap and ranges from zero to unity, reaching the latter limit when the two patterns become identical.

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50

DiMasi, E., and M. Sarikaya. "Synchrotron x-ray microbeam diffraction from abalone shell." Journal of Materials Research 19, no. 5 (May 2004): 1471–76. http://dx.doi.org/10.1557/jmr.2004.0196.

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Microstructured biomaterials such as mollusk shells receive much attention at present, due to the promise that advanced materials can be designed and synthesized with biomimetic techniques that take advantage of self-assembly and aqueous, ambient processing conditions. A satisfactory understanding of this process requires characterization of the microstructure not only in the mature biomaterial, but at the growth fronts where the control over crystal morphology and orientation is enacted. In this paper, we present synchrotron microbeam x-ray diffraction (XRD) and electron microscopy observations near the nacre–prismatic interface of red abalone shell. The relative orientations of calcite and aragonite grains exhibit some differences from the idealizations reported previously. Long calcite grains impinge the nacre–prismatic boundary at 45° angles, suggestive of nucleation on (104) planes followed by growth along the c axis. In the region within 100 μm of the boundary, calcite and aragonite crystals lose their bulk orientational order, but we found no evidence for qualitative changes in long-range order such as ideal powder texture or an amorphous structure factor. XRD rocking curves determined the mosaic of calcite crystals in the prismatic region to be no broader than the 0.3° resolution limit of the beamline’s capillary optics, comparable to what can be measured on geological calcite single crystals.

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