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

An organic nonlinear optical material, 3-methyl-4-methoxy-4′-nitrostilbene (C16H15NO3), 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 77 observed reflections with 2θ up to 82° are reported. The powder diffraction data have been evaluated, and the figures-of-merit are reported. The unit cell parameters least-squares refined from 30 non-overlapping peaks of the orthorhombic compound with a Aba2 space group are a=15.7882(3) Å, b=13.4892(4) Å, c=13.3940(2) Å, V=2852.5(4) Å3, Z=8, Dx=1.254 g/cm3. The powder diffraction results are in a agreement with those obtained from single-crystal structure data.

The two germanates K2MgGeO4 and K2CdGeO4 have been synthesized by solid-state reaction. These compounds are isostructural with K2ZnGeO4, space group Pca21 (No. 29), Z=8. Unit cell parameters were determined: for K2MgGeO4a=11.1810(11), b=5.5708(6), c=15.8694(16) Å, V=988.5(3) Å3 and for K2CdGeO4a=11.4777(24), b=5.7155(7), c=16.1732(17) Å, V=1061.0(5) Å3. Powder diffraction data are reported.

X-ray powder diffraction data and refined unit cell parameters for the (Bi, Pb)2Sr2Ca2Cu3Ox (2223) superconducting phase, indexed using incommensurate modulation principles, are reported. Comparison of the results obtained with one- and two-component modulation wave vectors showed that the two-component modulation wave vector is superior for indexing the satellite reflections. A two-component wave vector indexing result seems likely when only the powder diffraction data are considered.

A simple device was developed for a moisture-proof X-ray diffraction analysis. The device consists of a simple plastic ring where one side was glued on with a thin film to let in the X-ray beam and the other side was covered with grease to seal onto a base plate. This device was later optimized by selecting a good adhesive to glue on the film, a very effective film to minimize the moisture intake, and an optimum ring height to maximize the X-ray intensity. Finally, this simple device was successfully verified that it can protect the anhydrous CaCl2 (hydrophilite) up to 4 days in ambient air.

Samples of airborne particulate were collected at the “El Ingenio” site in Castellón (Spain) using a cascade impactor sampler. Quantitative analysis of present phases in the aerosol was performed using the full-pattern fitting Rietveld method. Quantitative information was obtained from refined individual scale factors and unit-cell volumes, obtained with a Rietveld refinement program. Quartz, calcite, and gypsum were encountered as major phases, and their size distribution and concentration in the atmosphere were calculated.

The anhydrous and hydrated lithium monoborates have been studied. The most hydrated phase is LiBO2·8H2O; its structural formula in the P3 space group is Li(H2O)4B(OH)4·2H2O. Refinement of the cell parameters yielded the following results: a=6.5483(5) Å, c=6.1692(7) Å with F(30)=64(0.015, 32), Z=1, and Dx=1.402 g/cm3. This phase gives LiB(OH)4 by spontaneous dehydration. An X-ray powder diffraction study of LiB(OH)4 as a function of temperature indicated three poorly crystallized hydrates. Two of these hydrates have the formula LiBO2·0.3H2O; the other, LiBO2·xH2O, has an undetermined water content. Crystal data for α-LiBO2 have been obtained: a=5.8473(10) Å, b=4.3513(6) Å, c=6.4557(10) Å, β=115.08(1)°, F(27)=58.5(0.001, 41); space group P21/c, Z=4, and Dx=2.18 g/cm3. β-LiBO2 does not exist but corresponds to the α-LiBO2 form observed at 600 °C. Numerous other LiBO2 forms reported recently have not been found.

In this paper we propose a fitting procedure to describe the bandpass effect on all x radiation that passes through a focusing graphite monochromator used on the diffracted beam. The proposed bandpass function is: M(2θ)=1/(1+Kmon1sKmon2), with s=(2 sin θ)/λ, where Kmon1 and Kmon2 are constants which have been refined by means of a Rietveld analysis, using a physically modeled background (Riello et al., J. Appl. Crystallogr. 28, 115–120). We have investigated two polycrystalline powders: α-Al2O3 and a mixture of α and β-Si3N4. The so-obtained bandpass functions for these materials are close enough to conclude that they depend only on the used experimental setup (in the present case the X-Pert-Philips diffractometer with a graphite focusing monochromator). Knowledge of the bandpass function is important to suitably model the Compton scattering, which is a component of the background scattering. The present procedure allows one to avoid the direct experimental determination of the bandpass function, which requires the use of another monochromator (analyzer) and another tube with an intense white spectrum.

A new phase in the system BaO-MnO-SiO2 obtained by a pyrosynthetic method has been investigated using selected area electron diffraction (SAED), electron probe microanalysis (EPMA), and X-ray powder diffraction. The lattice parameters and a possible space group of the phase with a general composition BaMnSiO4 were determined as follows: a=5.370(2), b=18.447(7), c=8.498(5) Å, Z=8, Space Group Pmc21.

It is known that solids with composition Na3Zr2Si2PO12 heated at 1200 °C crystallize in the nasicon structure. This material shows a high ionic conductivity that represents an interesting improvement in the field of solid electrolytes. Our experimental results allow to establish for the first time that nasicon structures are stable along the compositional join Na3Zr2−x/4Si2−xP1+xO12 with x extending from 0 to 1.667. These structures are characterized by a Zr underoccupation of octahedral sites and a constant number of Na+ ions. This fact envisages a possible application of these materials in the field of ceramic sensors and ionic conductors.

X-ray diffraction data has been collected from biological calcific mineral associated with human bone, breast tissue, ureteric calculi, heart valve, and aorta. All the materials are shown to have a nominal calcium hydroxyapatite structure and Rietveld analysis has been performed to extract microstructural information. All refinements achieved a final Rwp value of <10%. The lattice parameter ranges are a=9.375(3)(breast)−9.4316(8)(heartvalve), c=6.866(1)(uretericcalculi) −6.899(1)(rib), and crystallite size range from 40 Å (breast) to 99 Å (ureteric calculi). A correlation between crystallite size estimates from this Rietveld analysis and line profile methods is demonstrated. The results are supported by an infrared study and previous data from alternative techniques. Thus, it is demonstrated that the microstructure of these materials may be characterised by application of the Rietveld method.

The thermal decomposition of barium bis(citrato)oxotitanate citrate heptahydrate, a molecular precursor of BaTiO3 fine powders is studied by temperature-dependent x-ray powder diffraction and thermogravimetry. A thorough investigation of the dehydration stage is presented. Three crystalline phases containing seven, three, and two water molecules, respectively, are identified from their powder diffraction pattern. The results of pattern indexing are presented and discussed in terms of parameter relationships.