The Ba2.64Ta11.25O30.81was prepared by conventional solid-state reaction technique as a single phase. It was found that the compound crystallizes in the tetragonal system, space group P4/mbm (No. 127) and unit-cell parameters are a = 12.508 59(8) Å, c = 3.912 81(2) Å, V = 612.218(7) Å3, and Z = 1. The crystal structure of the Ba2.64Ta11.25O30.81 phase is found to be closely related to the tetragonal tungsten bronze structure type, comprising interstitial (TaO)+ inclusions. Reference data were derived from the Rietveld analysis and reported here.

The human eye is continuously exposed to the environment yet little is known about how much of toxins, specifically heavy metals are present in its different parts and how they influence vision and acuity. To shed light into this subject, aqueous humor and lens samples were collected from 14 cataract patients to study the presence and concentration of selected metals in the eye. Subjects undergoing routine cataract surgery were consecutively enrolled for study by simple random sampling. Prior to surgery, subject demographic were compiled. The surgical procedure involved small incision cataract removal using phacoemulsification. During the procedure, a small aliquot of aqueous humor was retained for analysis, whereas homogenized lens fragments were obtained during phacoemulsification. A balanced salt solution was used as control for each set of samples. Both ocular specimens were analyzed by total reflection X-ray fluorescence spectrometry after dilution and addition of an internal standard. The data obtained show substantial variations in elemental signature between the two media (aqueous humor and lens) and the patients themselves. Most commonly found heavy metals in both types of media were chromium and manganese. Barium was found in the lens, but not in aqueous tissue, whereas nickel was found only in the aqueous humor. Concentrations were generally higher in aqueous samples. Further study and increased sample size are required to more accurately elucidate the relationship between systemic and ocular metal accumulation and the impact of metal accumulation on measures of visual function and ocular disease.

Preparation, analytical characterization, and crystal structures of N,N′-bis(thiophen-2-ylmethyl)ethane-1,2-diaminium hydrochloride (1) and of its gold derivative, N,N′-bis(thiophen-2-ylmethyl)ethane-1,2-diaminium tetrachloroaurate(III) (2) are reported. Compound (1) was obtained by reduction of the Schiff base N,N′-bis(thiophen-2-ylmethyl)ethane-1,2-diamine followed by HCl solution addition, whereas compound (2) was prepared reacting (1) with K[AuCl4] in aqueous solution. Compound (1) crystallizes in the orthorhombic system with space group Iba2 and cell parameters a = 29.856(1), b = 5.1372(2), and c = 10.1635(4) Å. Crystals of (2) belong to the monoclinic system with space group P21/c and cell parameters a = 11.0829(1), b = 9.5852(1), c = 11.6054(2) Å, and β = 75.49(1)°. Both structures contain diprotonated organic moieties, counterbalanced by hydrogen-bonded Cl−, or [AuCl4]− ions, in compounds (1) and (2), respectively.

X-ray powder diffraction data, unit-cell parameters and space group for a new bis(β-diiminato) Cu(II) complex, C48H62CuN4O4 are reported [a = 13.330 (3) Å, b = 11.137(2) Å, c = 8.832(2) Å, α = 78.88(2), β = 94.73(2), γ = 114.55(2), unit-cell volume V = 1170.26 Å3, Z = 1, and space group P − 1]. All measured lines were indexed and are consistent with the P−1 space group. No detectable impurity was observed.

Thiocolchicoside (THC) is an important active pharmaceutical ingredient (API) used as a muscle relaxant because of its anti-inflammatory and analgesic effects. The only entry for a THC-related compound present in the Cambridge Structural Database (CSD) corresponds to a THC ethanol solvate hydrate (refcode: THCLCS). The diffraction pattern recorded for the THC raw material (C27H33NO10S·xH2O) is different from the pattern calculated using the THCLCS crystallographic data contained in the CSD. The indexing of the THC raw material pattern, produced an orthorhombic unit cell with a = 28.018(7) Å, b = 12.519(2) Å, c = 8.519(1) Å, and V = 2988.01 Å3. All the diffraction maxima of the powder pattern of a phase recrystallized in water (C27H33NO10S·2H2O) can be indexed in an orthorhombic cell with a = 25.264(4) Å, b = 13.537(3) Å, c = 8.553(1) Å, and V = 2925.12 Å3. Thermogravimetric analysis shows that this compound is a dihydrate phase. Upon heating, a new anhydrous phase (C27H33NO10S) with a monoclinic cell and unit cell parameters: a = 17.090(5) Å, b = 19.485(5) Å, c = 8.526(3) Å, β = 100.30(2)°, and V = 2793.34 Å3 is obtained.

The use of high-speed detectors made X-ray diffraction (XRD) become an important tool for process control in mining and metal industries. Decreasing ore qualities and increasing prices for raw materials require a better control of processed ore and a more efficient use of energy. Traditionally quality control of iron ore sinter has relied on time-consuming wet chemistry. The mineralogical composition that defines the physical properties such as hardness or reducibility is not monitored. XRD analysis in combination with Rietveld quantification and statistical data evaluation using partial least-squares regression (PLSR) has been successfully established to determine the mineralogical composition and the Fe2+ content of iron ore sinter within an analysis time of less than 10 min per sample. A total of 35 iron ore sinter samples were measured and evaluated using PLSR and the Rietveld method. The results were compared with wet chemistry data. PLSR results show accuracy for the Fe2+ content of ±0.14%. No pure phases, crystal structures, or complex modeling of peak shapes are required. The Rietveld method was used to quantify the total phase composition of the samples. The Fe2+ content could be calculated from all phases present. Both methods take the full XRD pattern into account and can be simultaneously applied on the same measurement. PLSR was found to be the more robust method if only Fe2+ results are required. The Rietveld method helps predict other parameters such as the compressional strength of the sinter by monitoring all existing phases (e.g., larnite, C2S, or silico-ferrite of calcium and aluminum phases).

X-ray diffraction (XRD) was used to determine the temperature at which the transformation of Ce2O(CO3)2·H2O to ceria (CeO2) occurs under both a flow of nitrogen and air as a function of temperature. The Ce2O(CO3)2·H2O synthesised from Ce(NO3)3·6H2O and urea was further investigated using thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). XRD results indicate that, under a flow of nitrogen, CeO2 is formed at temperatures greater than 500 °C and that this occurs via an as yet unidentified intermediate phase, which is present between 430 and 540 °C. Results obtained by the XRD correspond to those obtained using TGA, which show weight  losses commencing at 430 and at 465 °C. No further weight loss occurs above 540 °C, because of the formation of CeO2 as the stable product. The crystallite size was also determined and observed to increase with increasing temperature. Under a flow of air the transformation occurred at a lower temperature, as CeO2 was formed at 250 °C. SEM and TEM reveal the particles have a rod-shaped morphology which is retained after calcination. These results may be used to optimise synthesis methods to minimise crystallite size growth and reduce sintering that is undesirable in many applications, particularly catalysis.

Analytical polarized energy-dispersive X-ray fluorescence (PEDXRF) spectrometry (PEDXRFS) represents a substantial advancement over conventional XRF. The higher signal-to-noise commensurate with background lowering and better energy resolution, permits trace analysis for elements with Z ≥ 11. Concomitantly, improvements in analytical software based on the fundamental parameters (FP) approach have improved accuracies and precisions for standard-less analysis (SLA). Two ceramic and soil standard reference materials (SRMs), 98a-Plastic Clay and GSS-1 powders, differed in their intrinsic matrix properties of grain size, bulk, and surface monolayer densities as well as the elemental concentrations. The SRMs were analyzed as powder and as pellets compacted under the same pressure conditions to double the bulk density. Different geometries represented by the sample cup (10, 15, and 24 mm) and pellet (10, 15, and 25 mm) diameters with the same sample thickness (with differing masses and aspect ratios), as well as (for powder samples only) identical low masses (0.5 g) but with varying thicknesses, were analyzed. PEDXRFS combined with TURBOQUANT® (TQ) as SLA-FP enables good quantitative analysis for powders (Z ≥ 13) even for masses significantly lower than recommended, for soil–ceramic samples. Pellets (Z ≥ 12) yielded the best accuracy factor (AF) at high aspect ratio and thicknesses of the matrix analytical depth. Binder in pellets depreciates the AF. TQ needs to adequately quantitate matrix interferences effects, to improve accuracy in the analysis of low atomic numbers, e.g. Na and Mg.

Veatchite polytypes were properly identified from several localities relying solely on micro powder diffraction data. Diagnostic differences in their respective calculated patterns gave reliable identification results when compared with measured data. This permitted the confirmation of co-existing veatchite-1A and -2M on the same specimen from the Billie Mine, Inyo County, California as flat elongated crystals (-1A) and flat rhombic plates (-2M), respectively. On the specimen from the Sterling Borax Mine (Lang), type-locality for veatchite-2M, the polytype veatchite-1A was confirmed from radiating rhombic plates. From the type specimen for veatchite-1A (rhombic plates), collected from the borate deposit in Emet, Turkey, an additional unknown polytype of this mineral was discovered, but lacks suitable material for a complete characterization. At the Penobsquis deposit near Sussex in New Brunswick, Canada, only veatchite-2M was encountered. The area between 20 and 25°2θ holds the following diffraction signatures: -1A (two sets of double peaks at approximately 21.5 and 24.5°2θ), -1M (single peaks at 20 and 23°2θ) and -2M (double peaks at 20 and 23°2θ). The unknown polytype from Emet, Turkey differs from polytype-1A in that same range by having single peaks at the 21.5 and 24.5° instead of double peaks.

A new quaternary compound PrAlFeNi3 was synthesized and studied by means of X-ray powder diffraction technique. The powder pattern of PrAlFeNi3 was indexed and refined, giving a hexagonal structure, space group P6/mmm (No. 191) with the CaCu5 structure type, a = 5.1132(2) Å, c = 4.0737(1) Å, V = 92.19 Å3, Z = 1, ρx = 7.20 g cm−3, F30 = 173.61 (0.0054, 32) and RIR = 0.77.

Diketopyrrolopyrrole (DPP) is a pigment widely used in modern paints for industrial and artistic applications. Identification of this pigment in paint for art authentication and forensics has previously been accomplished with gas chromatography/mass spectrometry or Laser Raman. Three commercial artist's paints containing DPP were analyzed by x-ray diffraction (XRD). Alpha phase DPP was identified in two of the samples, barite extender the only crystalline component identified in the other sample. In conclusion, XRD analysis of paint samples can identify DPP, as can other organic analyses, but has the advantage of being non-destructive and also identifying the crystal structure. However, the fact that in one sample only extender could be identified does impose some limitations on the analysis of paints.

Synchrotron X-ray diffraction images are increasingly used to characterize not only structural and microstructural features of polycrystalline materials, but also crystal preferred orientation distributions. Diffraction data can be analyzed quantitatively and efficiently with the Rietveld method and here the detailed procedure is reported from the experiment to the calibration of the two-dimensional detector and full analysis of the sample. In particular, we emphasize the advantage of doing the calibration inside the Rietveld least-squares fitting instead of a preliminary graphical calibration. Then the procedure is described to quantify crystal preferred orientations with the Rietveld method implemented in software “Materials Analysis Using Diffraction”. The process is illustrated for a US “nickel” coin, a 75 at.% copper 25 at.% nickel alloy with face-centered cubic structure and a strong cube texture.

Rietveld-based quantitative X-ray diffraction (QXRD) has been extensively used for mineralogical characterization in order to understand the reaction chemistry, and kinetics of minerals leaching and formation. This work presents examples where QXRD has been applied to understanding fundamental aspects of these two processes. Firstly, the co-processing of nickel laterites and sulphidic materials has the potential to offer several advantages that include the use of lower grade (including non-smeltable) concentrates, improvement in the rheological behaviour of the blends, and reduction in the use of sulphuric acid. The leaching kinetics and chemistry of mixed nickel laterite ore and sulphide concentrate were explored by the QXRD analysis of feed materials and, intermediates and final leach residues produced using controlled oxidation rates. Under high temperature (250 °C) and pressure oxidation (~40 to 45 atm.) conditions, sulphide minerals in the nickel concentrate underwent several oxidative hydrothermal transformations, and ferrous iron was oxidized and precipitated primarily as hematite. High recovery of nickel can be achieved with low acid consumption under these conditions. Secondly, iron precipitation/removal is an important down-stream process in hydrometallurgy. Moderate concentrations of ferrous iron can be oxidized using micro-organisms with oxidation rates several orders of magnitude faster compared with abiotic oxidation at ambient temperature and pressure. QXRD and chemical analysis have indicated that after oxidation, iron at pH ~2 mostly precipitates as jarosite with various amounts of K+, Na+, NH4+, and H3O+ incorporated into the structure. Bio-catalysed iron removal can be achieved with minimum copper and nickel losses at relatively low pH conditions.

A very efficient analytical method using an automated fusion machine as sample preparation tool and a wavelength-dispersive X-ray fluorescence (WDXRF) spectrometer for the determination of all the elements of interest for the iron ore industry has been optimized from the ISO 9516-1 standard method. This updated method allows for the simplification of both laboratory and spectrometry processes and so, in comparison with the original International Organization for Standardization (ISO) method, becomes less restrictive in practice. This method was used to prepare a large variety of iron ores and exploration samples from all over the world. Results of the prevailing XRF application based on pure oxide standards as described in the ISO standard method are compared to the results of a unique XRF calibration application based on certified reference materials (CRMs) for iron ores and iron ores exploration materials. The universal sample preparation fusion method for iron ores and exploration samples developed during the first phase of this project was used to select and evaluate a set of CRMs. Selected throughout the world from well-recognized sources, the chosen set of CRMs allows a wide coverage for all the elements of interest of the iron ore industry, excluding tin oxide. This fusion method allows a matrix match for materials from different origins. A critical evaluation of precision and accuracy has been performed against the ISO standard method. Reference materials not included in the calibration (control samples) was also investigated for accuracy evaluation. Furthermore, comparisons will be made between the data collected from this fusion method implemented in combination with a Bruker S4 Explorer WDXRF Spectrometer, and the analytical requirements of ISO. All deviations from the prevailing standard method parameters (calibration, standards, flux, Fluxer, etc.) will also be pointed out and discussed.

Diffraction data of calcite were collected using a conventional Bragg–Brentano diffractometer, which is a convenient, low-cost, and highly popular in-house instrument, and its crystal structure was refined by the Rietveld method. This paper shows how one treats preferred orientation and how different refinement strategies affect the accuracy of the result.

Early in September 2013, only a few months away from the International Year of Crystallography (2014), nearly 230 scientists from more than 15 different Countries gathered in Como, for an International Conference co-organized by the Italian, Spanish, and Swiss Crystallographic Associations, presenting their most recent crystallographic results in variety of fields, in basic and applied Science. This brief account highlights the topics discussed during the conference, and the future of the European crystallographic research, with its relevance to distinct fields of physics, chemistry, biology, materials, and earth science, as well as in preservation of cultural heritage.

As a consequence of substantial advances in computer-aided design and manufacturing technology, engineering parts are no longer restricted to combination of simple geometrical shapes. Implementing complex curved surfaces in engineering components in combination with finite-element geometry optimization has become a prevalent means of designing a part. Measuring residual stresses using X-ray diffraction (XRD) on complex curved surfaces requires further development of current measurement methods. Here we investigate how a laboratory XRD system equipped with a five-axis stage and two-dimensional detector can execute sin2ψ residual stress measurements on curved surfaces. Shadowing that blocks the diffracted beam to reach the detector was avoided using proper rotations and tilting of the sample. A standard video-laser alignment system commonly used to manually place the sample in the center of diffraction was used to also generate virtual maps of the sample's curved surfaces on a fine mesh grid. The geometry was then used for setting the required rotations and tilt angles. A set of diffraction frames collected using this method on a model zirconia dental ceramic, afforded the opportunity to superimpose phase and stresses on a complex geometry. This is a step forward for the XRD technology, and its usefulness applies to many different industries.

The 18th International Symposium on the Reactivity of Solids (June 9–13, 2014 in Saint-Petersburg, Russia) brought together 137 researches from 18 countries, from crystallographers to electrochemists, to discuss the new materials design, advanced methods of preparation and characterization, mechanisms of reactions involving solids, structure–property relations, and new horizons of the materials application. What emerged from the meeting was an understanding that even if up-to-date solid state chemistry cannot be limited to organic, inorganic, or physical one, different groups of researches can understand each other and find a way for collaboration. More than half of the talks were devoted to energy production and storage problems, where the researcher should take into account not only just the chemistry of solid material, but also its crystalline structure, surface morphology, and even the bath liquid phase and interface properties. It means that only the interdisciplinary partnership can lead to outstanding results.

The yttrium-based metal–organic framework, Y(btc) (btc = 1,3,5-benzenetricarboxylate), shows moderate uptake of methane (0.623 mmol g−1) and molecular oxygen (0.183 mmol g−1) at 1 bar and 308 K. Neutron powder-diffraction data for the guest-free, CD4-, and O2-loaded framework reveal multiple adsorption sites for each gas. Both molecular guests exhibit interactions with the host framework characterised by distances between the framework and guest atoms that range from 2.83 to 4.81 Å, with these distances identifying interaction most commonly between the guest molecule and the carboxylate functional groups of the benzenetricarboxylate bridging ligand of the host.