X-ray powder diffraction data, unit-cell parameters, and space group for deoxyschisandrin, C24H32O6, are reported [a = 13.083(3) Å, b = 19.563(9) Å, c = 8.805(6) Å, β = 90.472(0)°, unit-cell volume V = 2253.82 Å3, Z = 4, and space group P21]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurity was observed.

In present investigation, effect of modulation and machining parameters on deformation level of the chips produced during modulation assisted machining (MAM) has been studied. It is shown that disruption in tool-chip contact during modulation assisted machining helps in the formation of discrete chips. Size and shape of the particles produced in MAM can be controlled by varying modulation and machining conditions. Particulates of different shapes and sizes ranging from 100 µm to 5 mm with an aspect ratio of ~10 were produced using MAM. The morphology of the particulates produced was characterized by scanning electron microscope (SEM). Deformation in chip particulates was investigated using X-Ray diffraction. The crystallite size and internal strain in particulates were evaluated using Scherrer and Williamson-Hall methods respectively. The crystallite size of the particulates was found to decrease with decrease in their size, whereas internal strain in particulates was observed to increase with decrease in their size. Furthermore, the length of particulates was observed to decrease with an increase in the ratio of frequency of modulation (fm) to frequency of workpiece rotation (fw). However, the corresponding change in microstrain and crystallite size was insignificant with change in this ratio.

Six A-type zeolites: NaA, MnNaA, CoNaA, NiNaA, ZnNaA, CdNaA have been characterized by X-ray powder diffraction. The zeolites with selected divalent cations have been synthesized by a very careful ion-exchange process using very high quality NaA zeolite. Experimental 2θ peak positions, relative peak intensities, values of d and Miller indices as well as a unit cell parameter are reported.

X-ray powder diffraction (XRD) is utilized for the determination of polymorphism in crystalline organic materials. Though convenient to use in a laboratory setting, XRD is not easily adapted to in situ monitoring of synthetic chemical production applications or thin film depositions. Near-infrared spectroscopy (NIR) can be adapted to in situ manufacturing schemes by use of a source/detector probe. Conversely, NIR is unable to conclusively define the existence of polymorphism in crystalline materials. By combining the two techniques, a novel simultaneous NIR/XRD instrument has been developed. During material’s analysis, results from XRD allowed for the determination of the existence of polymorphic phases, and NIR data were collected as a fingerprint for each of the observed polymorphs. These NIR fingerprints allowed for the development of a library, which can be referenced during the use of a NIR probe in manufacturing settings. The NIR/XRD instrument was also used to monitor materials during exposure to ambient air. XRD can detect crystalline phase changes and NIR can monitor solvent loss and/or water uptake.

Verification of materials is an increasingly important need in pharmaceutical distribution. XStream Systems, Inc. has developed an energy dispersive X-ray diffraction (EDXRD) system which can quickly verify crystalline pharmaceuticals in the distribution cycle. Materials may be in solid or powder form and the technique is nondestructive. Unlike angular X-ray diffraction (AXRD), a “white” X-ray beam between 20 and 80 keV is used. This energetic beam can penetrate through relatively thick materials, diffracting from crystallites within the samples. Materials can be observed even when they are located within opaque, sealed containers. That is, for most cases the drugs can be examined in their sealed, packaged vials without any sample preparation. The tabletop unit uses a confocal geometry to maximize the X-ray intensity from a relatively low-powered, air-cooled X-ray source. The beam is collimated by a circular slit assembly before the sample. A similar slit assembly after the sample collimates the diffracted beam. A single, state-of-the-art, CdTe solid-state detector with a multichannel analyzer is used to process the diffracted signal. This collimation system interrogates a doughnut-shaped volume within the sample under test. One of the design goals was to develop a unit that is capable of performing quick verification or detection of complex materials and mixtures at a number of points along the distribution paths yet can be operated by personnel with minimal scientific knowledge. Rapid identification of unknowns is possible using neural network search algorithms or pattern matching techniques. The Material Recognition Software Engine (MRSE) utilizes a localized SQL database to store and process the raw spectra data. The MRSE takes the sample data and determines if it matches any known patterns within its database. This engine has demonstrated that it can verify a number of drugs within 30 s with better than 97% accuracy.

The crystallographic data of YBa2Cu3O7−δ, Y2BaCuO5, BaCu2O2, and YBa4Cu3O9 at high temperatures and p(O2)<10 Pa have been derived on the basis of HT-XRD measurements. Whereas Y2BaCuO5 expands nearly isotropically, YBa2Cu3O7−δ and BaCu2O2 show anisotropic expansions. Furthermore, the first decomposition step of the considered compounds at p(O2)<10 Pa was observed. BaCu2O2 melts congruently at T ≍ 1273 K and Y2BaCuO5 decomposes via a peritectic reaction into Y2O3, Y2BaO4 and melts at T ≍ 1323 K. A solid-state reaction into Y2BaCuO5 and BaCu2O2 was indicated for YBa2Cu3O7−δ at T ≍ 1123 K. Because YBa4Cu3O9 becomes unstable at T ≍ 1123 K, this compound cannot be formed by the primary decomposition reaction of YBa2Cu3O7−δ

Synthesis and structure of two phosphates belonging to the ternary Sb2O5–In2O3–P2O5 system are realized. Structures of SbV1.50InIII0.50(PO4)3 and (SbV0.50InIII0.50)P2O7 phases, obtained by solid state reaction in air at 950 °C, were determined at room temperature from X-ray powder diffraction using the Rietveld method. SbV1.50InIII0.50(PO4)3 have a monoclinic (space group P21/n) distortion of the Sc2(WO4)3-type framework. Its structure is constituted by corner-shared SbO6 or InO6 octahedra and PO4 tetrahedra. Monoclinic unit cell parameters are a=11.801(2) Å, b=8.623(1) Å, c=8.372(1) Å, and β=90.93(1)°. (Sb0.50In0.50)P2O7 is isotypic with (Sb0.50Fe0.50)P2O7 and crystallizes in orthorhombic system (space group Pna21) with a=7.9389(1) Å, b=16.0664(2) Å, and c=7.9777(1) Å. Its structure is built up from corner-shared SbO6 or InO6 octahedra and P2O7 groups (two group-types). Each P2O7 group shares its six vertices with three SbO6 and three InO6 octahedra, and each octahedron is connected to six P2O7 groups.

Possibilities and restrictions of least-square methods for mica cell refinement are briefly described. If diffractometric raw data are precise and accurate, and if geometrical errors are properly corrected, a cell refinement (determination of ao, bo, cO, β) can be carried out rapidly, but the reliability of obtained data has to be evaluated carefully.

A new ternary compound Dy5Co6Sn18 was synthesized and studied. The crystal structure of Dy5Co6Sn18 was determined using the Rietveld refinement method. The compound was found to crystallize in tetragonal space group I41/acd, Tb5Rh6Sn18-type structure, with a=13.5598(3) Å, c=7.1470(5) Å, Z=8, and Dcalc=8.789 g/cm3. Measurements of magnetic susceptibility and electrical resistivity on polycrystalline samples were also performed. The Curie–Weiss law was followed, with θp=−15.7 K and μeff=10.61μB. Dy5Co6Sn18 is a spin-glass with a freezing temperature of 6.5 K.

ZnSe-based heterostructures grown on GaAs substrates have been investigated for use in pin-diode LED applications. In this study, a conventional Bragg-Brentano diffractometer (BBD) has been used to screen samples for phase identification, crystallite size, presence of polycrystalline ZnSe, and initial rocking curve (RC) analysis. A limitation of the conventional diffractometer is that the smallest RC full width at half maximum (FWHM) that can be achieved is 500 to 600 arc sec. As deposition parameters are optimized and the RC limit of the conventional diffractometer is reached, analysis is moved to a four-bounce high-resolution diffractometer (HRD). Although more time for analysis is required, using the HRD has a RC resolution advantage, where RCs of <20 arc sec are obtained for neat GaAs wafers. Combining the BBD and HRD instruments for analysis of ZnSe films grown on GaAs substrates allows for an efficient means of high sample throughput combined with an accurate measurement of film alignment.

Potassium calcium phosphate, KCa PO4.H2O, has been investigated by means of X-ray powder diffraction. Unit cell dimensions were determined from diffractometer data obtained with strictly monochromatized Cu Kα1 radiation, by indexing programs. A C-centered monoclinic cell was found: a =7.5834(9) Å, b = 8.1568(11) Å, c = 7.6541(8) Å, β= 102.975 (9)°.

Nanocrystallized oxide precursors of colored (oxy)nitrides related to the system Yb-(Zr-W)-O have been successfully prepared using a chimie douce process—the amorphous citrate route. The process involves first a formation of fine and homogeneous powdered solids obtained by calcination at 600 °C, a temperature much lower than that of the conventional solid-state method. At this stage, the X-ray diffraction patterns exhibit large line broadening effects. Finally, two well-crystallized and pure quaternary oxides have been readily obtained by heating and under annealing conditions at 850 and 900 °C for 12 h. For one of the patterns, all the X-ray diffraction lines can be easily indexed to a cubic phase with the fluorite structure conforming to the Fm3m space group [Yb2Zr1.21W0.41O6.65◻1.35 called C-phase: a=5.1864(2) Å]. The second phase adopts the sheelite-type structure [Yb2ZrWO8 called T-phase: space group I41/a, a=5.1584(5), and c=10.8246(6) Å]. By taking into account the present compositions determined by EDS measurements, Rietveld structure refinements produce final RB factors of 0.015 and 0.044, and Rwp factors of 0.069 and 0.089, respectively. In order to characterize the microstructure of the materials (crystallite size and lattice distortion) at the nanometer scale, a study based on diffraction line broadening analysis applying the whole pattern refinement method was also undertaken with confidence. The results show smooth angular variations of the values of FWHMs, indicating that the microstructural properties are isotropic for the cubic and tetragonal oxides. More precisely, the results indicate that whatever the profile fitting approach used (“profile matching” procedure and Rietveld method), the reliability factors Rwp are systematically better with a combined size strain than with zero strain considerations. The strain magnitudes observed for the C-phase-850 °C as well as for the T-phase-900 °C should be viewed as realistic strain.

Titanium oxycarbonitride was observed to form during the carbothermic reduction of TiO2 in the presence of nitrogen. A powder diffraction pattern for this phase which is isomorphous with TiC, TIN, and TiO is presented. The crystal structure is further discussed in terms of the observed composition and lattice defects.

Nanostructuring is one of the effective approaches to lower the thermal conductivity of thermoelectric materials for improving its figure of merit. The nano-sized uniform skutterudite Co1−xNixSb3 (x = 0, 0.05, 0.075, 0.125, 0.15, and 0.25) thermoelectric powders were synthesized in triethylene glycol solution by using CoCl2, NiCl2, and SbCl3 as precursors and NaBH4 as the reductant. Different synthesis conditions were studied to pursue pure and uniform skutterudite CoSb3 powders. The powders were characterized by X-ray diffraction, field emission scanning electron microscope, and energy-dispersive X-ray analysis. Experimental results show that a Ni-doped skutterudite Co1−xNixSb3 single phase was obtained at 290 °C for 12 h. The powders are spherical, small, and uniform. As x increases from 0 to 0.25, the unit-cell parameter a increases from 0.9044 to 0.9065 nm and the particle size increases from 10 to 30 nm.

New solid solution phases in the (Y,Ca)(Cr,Co)O3 system have been synthesized and characterized by powder X-ray diffraction. The selected compositions in this system were prepared by the modified Pechini method. Powder-diffraction patterns were prepared.

X-ray powder diffraction data are reported for a series of isomorphous compounds of [Ln2(CrO4)3(H2O)5]·2H2O, where Ln=La, Pr, Nd, Sm, or Eu. The compounds crystallize in monoclinic space group P21/c (No: 14) with Z=4. Refined unit cell parameters and indexed powder diffraction patterns are given.

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/.