The kalipyrochlore (K,Sr,Na,Ca,H2O)2−m(Nb,Ti)2−xO6−wY1−n, with (0<m<0.8, x∼0.2, w = 0 and 0.2<n<1) from Lueshe, Zaire is a defect pyrochlore species whose A-site weakly depleted. The measured powder diffraction is presented with a calculated figure of merit F(30) = 74.7(0.010,39). The structure has been refined by single-crystal from X-ray diffraction data collected on a Huber four-circle diffractometer and by Rietveld analysis from X-ray powder diffraction data. The slightly weathered crystal (studied by single crystal) has a cubic pyrochlore-type structure with the same atomic positions and a unit-cell parameter a = 10.603(5) Å, space group (S.G.): Fd3m. The highly weathered crystal (studied by Rietveld) has the same cubic pyrochlore-type structure except for the oxygen position. The oxygen moved from the 48f position with x, y, z equal to 0.284, 0, 0 to x = 0.308(5), y = 0.024(6) and z = –0.028(9). The cell parameter is a = 10.569(6)±0.0007 Å. These modifications of positions induce a distortion of the A-site into an hexagonal bipyramid and an elongation of the B-site along the c axis of the octahedron.

X-ray powder diffraction analysis of Diltiazem Hydrochloride C22H26N2O4S·HCl reveals that the compound crystallizes in an orthorhombic unit cell with the powder data unit cell parameters of a=9.08(1), b=42.09(4), c=6.03(1) Å, V=2305 Å3. The unit cell dimensions determined by single crystal diffraction analysis agree well with those of powder diffraction analysis. Samples prepared under different crystallization conditions yielded the same powder patterns.

This report is one of a series on the nomenclature for spectrochemical analysis issued by the International Union of Pure and Applied Chemistry. It concerns a new notation for X-ray emission lines and absorption edges, to be called IUPAC NOTATION, which replaces the existing Siegbahn notation. It is based upon the energy level designation and has the advantage of being simple and easy to apply to any kind of transition. Moreover, it is consistent with the notations used in electron spectroscopy.

The document first discusses the terms currently used in X-ray spectroscopy and then describes the principles of the IUPAC notation with reference to the X-ray levels and the X-ray transitions. The correspondence between Siegbahn and IUPAC notations for all X-ray lines is given in a table. Finally, the document gives the units and conversion factors used in the X-ray range.

Three isotopic orthovanadates MTh2 (VO4)3 with M = K, Rb, Cs have been syndiesized by solid state reaction. Single crystals of K Th2 (VO4)3 and Rb Th2 (VO4)3 were obtained. These compounds are isotypic with the corresponding orthophosphates: monoclinic, space group C2/c, Z = 4. Unit-cell parameters for die diree compounds were determined. Powder diffraction data for each phase are reported.

A Bi2O3 compound which is unknown to date has been synthesized at 800 °C on a BeO substrate. α-Bi2O3 at 800 °C undergoes a phase transition to a metastable new compound named ω-Bi2O3 which in turn transforms to stable δ-Bi2O3 at 900 °C. X-ray powder diffraction data were collected, indexed, and refined in order to obtain a unit cell (probable space group P1¯: a=7.2688(4), b=8.6390(6), c=11.9698(8) Å, α=87.713(6), β=93.227(6), γ =86.653(4)°. This compound is of interest for the thick films circuits and sensors technology.

An indexed powder diffraction pattern and related crystallographic data are reported for cefotaxime sodium salt: 5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, 3-[(acetyloxy)methyl]-7-[[(2amino-4-thiazolyl)(methoxyimino)-acetyl]amino]-8-oxo, monosodium salt, [6R−[6α,7β(Z)]], C16H16N5NaO7S2. The unit cell dimensions were determined from diffractometer methods, using monochromatic CuKα1 radiation, and evaluated by indexing programs. The monoclinic cell found for cefotaxime sodium was a=13.063(2) Å, b=8.916(2) Å, c=9.726(2) Å, β=107.34(2)°, Z=2, space groups: P21 (No. 4) or P21/m (No. 11), Dx=1.467 g/cm3.

This paper further confirms that the direct measurement of diffraction angles at different temperatures by using the X-ray diffractometer is better than measurement of the lattice parameters for the rapid and accurate determination of the linear thermal expansion of silicon. High purity silicon has the linear expansion coefficient, α= (2.45±0.05) × 10−6/°C at room temperature. This value does not change for doped P-type and N-type silicon.

With the help of Boulle's metathesis reaction, we have succeeded in preparing the compound [NH3(CH2)2NH3]2·P207. We describe its chemical preparation and main crystallographic features. The bis(ethylenediammonium) diphosphate salt is monoclinic, space group C2/c, with Z = 4. Unit cell parameters and powder diffraction data for this salt are reported.

YBa2Cu3O7–x films were deposited by chemical vapor deposition (CVD) onto single-crystal MgO, single-crystal Al2O3, and polycrystalline Al2O3 substrates, characterized before and after annealing, and tested for their superconducting properties. The preferred orientation in the films was analyzed (i) with pole figures and (ii) by comparison of experimental x-ray powder diffraction patterns with those calculated for the material using the March–Dollase function to model the degree of preferred orientation. Preferred orientation was significant in as-deposited films, with March coefficients ranging from 0.1–0.5 (random orientation would have a coefficient of 1.0). The (006) pole figures of the films on single crystal substrates exhibited uniquely symmetric patterns. On single-crystal MgO before annealing, a minor secondary orientation of (006) poles in the film was observed in a pattern consistent with the symmetry of major crystallographic directions of MgO. On single-crystal Al2O3 after annealing, a “dual orientation” phenomenon was observed. The high-temperature anneal destroyed the orientation and superconducting properties of the CVD films deposited at high temperatures.

XLENS is a traditional direct methods program working exclusively in reciprocal space. The distinctive feature of XLENS is the use of the modulus sum function as target function for the phase refinement. Due to its efficiency, robustness, and no need of weighting schemes, this function is specially well suited for treating powder diffraction data. The mathematical basis as well as the significance of the most important control parameters of the program will be described here. To illustrate how XLENS works, three different examples will be shown. Due to its simplicity, the modulus sum function can be easily combined with real-space filtering procedures to produce even more efficient crystal structure solving strategies.

A significant feature for the atomic structure of the intermetallic compounds Co2Al5 (hP28), monoclinic m-Co4Al13(mC(102-7.2) [notation according to Parthé etal. (1993)] and orthorhombic o-Co4Al13 (oP102) is the occurring of the filled pentagonal channels. Least-square refined lattice parameters as well as powder diffraction data are reported for these homeotypic phases.

2 Hydroxymethyl-2 methyl-1,3 propanediol tetrahydrate has been crystallised from aqueous solutions in the form of transparent tetragonal thin plates. The cell parameters of the unit cell were determined as a = 9.102(1) Å, c = 47.654(6) Å and the space group is I41/ a.

Solid liquid and reverse transformations have been studied by DSC, and a melting enthalpy of 185 kJ.kg−1 at 29.8° C determined.