X-ray powder diffraction data, unit-cell parameters, and space group for drospirenone, C24H30O3, are reported [a = 12.897(1) Å, b = 12.618(1) Å, c = 12.252(1) Å, α = β = γ = 90°, unit-cell volume V = 1994.13 Å3, Z = 4, ρcal = 1.229 g cm−3, and space group P212121]. All measured lines were indexed and are consistent with the P212121 space group. No detectable impurities were observed.

The crystal structure data have been determined by X-ray diffraction for three rare earth magnetic materials, Nd2Co14B, Pr2Co14B, and Pr2Fe14B. The data were evaluated with several computer programs desingned for that purpose. The crystal structure for Nd2Co14B and Pr2Fe14D determined by X-ray diffraction agree with those obtained earlier by neutron diffraction.

The Metals and Alloys Indexes, published by the International Centre for Diffraction Data, contain four indexes. These are: (a) the alphabetical formula index (AFI); (b) the Pearson symbol code index; (c) the common name index; and (d) the Strukturbericht symbol index. These indexes (which contain metals, alloys, and related phases in the Powder Diffraction File) have been designed to be used independently or in conjunction with the Powder Diffraction File to facilitate the characterization of materials. All data in these indexes have been critically reviewed. The organization, selection of materials, and use of alphabetical formulas are similar to those of standard metallurgical references such as Pearson or Villars and Calvert. The arrangement of the AFI promotes systematic searches for chemical analogs and assists users in locating possible matches when only partial chemical information is available. The structural indexes aid in characterization by correlations to prototype and related structures. Some applications of the indexes are given here.

The crystal structures of ruthenium oxides with the general formula Nd2−xMxRu2O7−y, where M is Cu or Ag, 0≤x≤0.25, were investigated. All compounds that were prepared exhibit the pyrochlore structure with a cubic unit cell. The compounds were characterized by X-ray powder diffraction, and single-phase structures were found for Nd2−xCuxRu2O7−y, x=0.1, 0.2, 0.25, and for Nd2−xAgxRu2O7−y, x=0.1, 0.15, 0.2. The relative metal concentrations were verified by EDS. The cell parameters were determined by advanced peak-position analysis and calibrated by a Si internal standard. Atomic positions and oxygen occupancies where refined by the Rietveld method. It was found that the cell-size modifications agree with the relations between ionic sizes.

This paper reports a reference X-ray powder diffraction pattern for a high-pressure phase, CaCo2O4, which has been reported recently to have a large Seebeck coefficient. The structure of CaCo2O4 is orthorhombic with space group Pnma, a=8.789(2) Å, b=2.9006(7) Å, c=10.282(3) Å, V=262.43 Å3, and Dc=5.62 g/cm3. This phase crystallizes in the CaFe2O4-type structure and consists of an edge- and corner-shared CoO6 octahedral network. The reference pattern has been submitted to the Powder Diffraction File (PDF).

New Ca8−xPbxCdBi(VO4)7 with the whitlockite-type structure were prepared by a standard solid-state method in air. Le Bail decomposition was used to determine unit-cell parameters. Structural refining was carried out by Rietveld's method. It is found that Bi3+ cations located partially in M1 and M2 sites along with calcium, while M3 site is settled in half by Pb2+-ions. Second-harmonic generation demonstrate highest non-linear optical activity and along with dielectric investigations indicate polar space group R3c.

A new compound Er0.33Sr1.67Ni0.8Cu0.2O4−δ (ErSr5Ni2.4Cu0.6O11) was prepared using the conventional solid state method and annealed at 1423 K in 1 atm of oxygen gas flow. The oxygen non-stoichiometry (δ = 0.47) was determined by iodometric titration. Rietveld refinement using powder X-ray diffraction data confirms that the sample adopts the K2NiF4-type structure (space group I4/mmm (Z = 2), a = 3.760 56(4) and c = 12.3889(1) Ǻ). The final reliability factors were: Rwp = 10.75%, χ2 = 2.51, Rp = 14.80%, RB = 4.77% and RF = 2.73%. Four probe electrical resistivity measurements were performed vs. temperature in the range of 320–540 K. A semiconducting behaviour over the whole range of temperature, with a maximum conductivity of 0.026 S cm−1 is observed at 439 K.

A nonlinear optical material 4-(N,N-dimethylamino)-3-acetamidonitrobenzene, (CH3)2NC6H3NO2NHCOCH3, has been characterized by X-ray powder diffractometer method. The experimental 2θ values corrected for systematic errors, the relative intensities, values of dexp and the Miller indices of the 46 peaks observed in the 5° to 51° 2θ range are reported. The powder diffraction data have been evaluated, and the figure of merit is F30 = 36.6 (0.016, 51). The unit cell parameter least-squares refined from 38 non-overlapping peaks of the monoclinic compound with a P21 space group are: a = 4.792(1)Å, b = 13.055(2)Å, c = 8.735(1)Å, β = 94.43(2)°, V = 544.8(1)Å3, Z = 2, and Dx = 1.36 gm/cm3. The powder diffraction results are in a good agreement with those obtained from single-crystal structure data.

Twenty-seven scapolite samples from various localities and with compositions between Me 6–93 were obtained using electron microprobe analysis (EMPA). Their unit-cell parameters were obtained using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and Rietveld structure refinements using space group P42/n. The EMPA data show the well-known discontinuity at Me 75. In addition, the unit-cell parameters, especially c, show a discontinuity at Me 75 (=five Al atoms per formula unit, apfu), ideally NaCa3[Al5Si7O24](CO3), where the scapolite solid solution is divided into two (Me% = [Ca/(Ca + Na + K)] × 100). A maximum c parameter value occurs at Me 37.5 (=four Al apfu ideally), where complete Al–Si, Na–Ca, and Cl–CO3 order occurs. The unit-cell volume, V, varies smoothly with Me% and Al apfu across the series.

A nonlinear optical material, N-(p-methoxy benzoyl)-N′(o-methyl phenyl) thiourea (C16H16N2O2S), has been characterized by X-ray powder diffraction. Experimental values of 2θ corrected for systematic errors, relative peak intensities, values of d, and the Miller indices of 90 observed reflections with 2θ up to 88° are reported. The powder diffraction data have been evaluated, and the figures-of-merit are reported. The least-squares refined unit cell parameters are a=26.7079(3) Å, b=6.7995(9) Å, c=19.2845(1) Å, β=121.39(4), V=2989.42(3) Å3, Z=8, Dx=1.334(8) g/cm3, space group P2(3).

Using high resolution powder neutron diffraction data, we show that there is a distinct anomaly in the structural noncentrosymmetry around the magnetic transition point TN for bulk and nanoscale BiFeO3. It appears that the structural noncentrosymmetry - which gives rise to the ferroelectric polarization - is suppressed anomalously by ~1% (of the average noncentrosymmetry at above the magnetic transition) in the bulk sample and by ~12% in the nanoscale sample as the magnetic transition is approached from higher temperature. This observation shows that the multiferroic coupling improves in the nanoscale sample which is expected to brighten the application prospects of nanoscale BiFeO3 in nanospintronics-based sensor devices.

PACS Nos. 75.70.Cn, 75.75.-c

An example of commercially available product, 2-(methylideneamino)acetonitrile (MAAN). This paper will address problems in discerning monomer–polymer ambiguity in organic compounds. Reliable three-step analysis of organic polymers will be proposed using the synergy of computational [density functional theory (DFT)] and experimental [infrared spectroscopy (IR); X-ray powder diffraction (XRPD)] techniques. First, possible conformations of monomeric and trimeric MAAN were calculated using stochastic search and DFT. Second, identification of the commercial sample was performed by comparing the measured IR spectrum with those calculated for monomer and trimer. Third, the examination of sample purity and structural analysis were carried out using XRPD data.

This paper reports the first successful synthesis and the structural characterization of nanocrystalline and stacking-disordered β-cristobalite AlPO4 that is chemically stabilized down to room temperature and free of crystalline impurity phases. Several batches of the title compound were synthesized and thoroughly characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectroscopy mapping in SEM, solid-state 31P nuclear magnetic resonance (31P-NMR) spectroscopy including the TRAPDOR method, differential thermal analysis (DTA), gas-sorption methods, optical emission spectroscopy, X-ray fluorescence spectroscopy, and ion chromatography. Parameters that are critical for the synthesis were identified and optimized. The synthesis procedure yields reproducible results and is well documented. A high-quality XRD pattern of the title compound is presented, which was collected with monochromatic copper radiation at room temperature in a wide 2θ range of 5°–100°.

This paper summarizes an oral presentation of the same title presented at the occasion of recognizing the “The 100th Anniversary of X-ray Spectroscopy” at DXC 2013. It gives an overview of the development in electronics with focus on (mainly) energy-dispersive X-ray detectors and related data processing. Naturally this has its origin in the early transistors and the first semiconductor junction detectors of the late 1940s. It was followed by refinement of semiconductor detector technology in general and particularly by the invention of Li-drifting and employment of low-noise field effect transistors until such devices matured sufficiently to be marketed by the late 1960s. Further improvement followed in resolution, speed, operability at room temperature, and development of junction arrays with imaging capabilities. An important aspect is the development of related software requiring affordable laboratory computers, programming languages, and databases of fundamental parameters. Today x-ray fluorescence analysis (and not only the energy-dispersive variant) is widely employed as an analytical tool for the traditional technical and industrial applications but notably also, at an expanding rate as well as variety, in other fields including environmental, medical, archaeological, space, arts, and many more.

The ICDD has developed a microanalysis tool to help scientists identify minerals from their elemental analyses, most typically micro-XRF or a microprobe analysis. Many minerals have characteristic elemental profiles that can often distinguish the mineral from others by their composition differences. In Release 2016 ICDD® PDF-4 databases 20 670 unique compositions have been identified out of 45 497 mineral and mineral-related entries. The application utilizes several common features of PDF® databases to enhance correct identification, most notably those formulas are expressed in weight and atomic percent, data sets are classified by mineral nomenclature and structural classifications, and most minerals have associated atomic and molecular structures. These crystal structures are very useful in determining compositional variants and solid solutions. The ICDD has developed algorithms that are analogous to the search/match processes used for powder diffraction identification. Data can be input as either the element or common oxide. To test the algorithm and graphics interfaces we compared results from the microanalysis module to published data from the Smithsonian Microbeam reference mineral collection. The software correctly identified 24/28 minerals by the highest merit score in the algorithm. In two cases, an isoelemental mineral was identified and in two other cases, the specimens had more elements than the reference standards hindering positive phase identification.

We report on the analysis of virtual powder-diffraction patterns from serial femtosecond crystallography (SFX) data collected at an X-ray free-electron laser. Different approaches to binning and normalizing these patterns are discussed with respect to the microstructural characteristics which each highlights. Analysis of SFX data from a powder of Pr0.5Ca0.5MnO3 in this way finds evidence of other trace phases in its microstructure which was not detectable in a standard powder-diffraction measurement. Furthermore, a comparison between two virtual powder pattern integration strategies is shown to yield different diffraction peak broadening, indicating sensitivity to different types of microstrain. This paper is a first step in developing new data analysis methods for microstructure characterization from serial crystallography data.

Polycrystalline samples of Ca2Zn2(V4O14) (I) and Pb2Cd2(V3O10)(VO4) (II) were synthesized using the nitrate–citrate method (I) and conventional solid state reaction (II). The structural refinement based on X-ray powder diffraction data showed that the crystal structure of (I) is characterized by monoclinic symmetry with unit-cell parameters a = 6.8044(1) Å, b = 14.4876(3) Å, c = 11.2367(2) Å, β = 99.647(1)° [space group P21/c (No. 14), Z = 4], and the crystal structure of (II) is triclinic with unit-cell parameters a = 7.03813(6) Å, b = 12.9085(1) Å, c = 6.99961(5) Å, α = 90.7265(5)°, β = 96.3789(5)°, γ = 94.9530(6)°, V = 629.470(8) Å3 [space group P$\bar 1$ (No. 2), Z = 2].