High-temperature X-ray diffraction with concurrent gas chromatography (GC) was employed in the study of iron disulfide (FeS2) cathode pellets disassembled from thermal batteries. When FeS2 cathode materials were analyzed in an air environment, reaction of the KCl and LiCl salt phases led to the formation of Li2(SO4) and KFe2S3 phases beginning at ~230 °C. These phases subsequently reacted to generate various forms of potassium iron sulfates in the 280–500 °C range, with the final products resulting in a β-Fe2O3 phase and K2(SO4). Independent simultaneous thermal analysis coupled with mass spectroscopy (MS) augmented the diffraction results and supported the overall picture of FeS2 decomposition. Both gas analysis measurements (i.e. GC and MS) from the independent experiments confirmed the formation of SO2 off-gas species during the breakdown of the FeS2. In contrast, characterization of the same cathode material under inert conditions showed the persistence of the initial FeS2 phase throughout the entire temperature range of analysis.

Advancements in computer technology have enabled three-dimensional (3D) reconstruction, data-stitching, and manipulation of 3D data obtained on X-ray imaging systems such as micro-computed tomography (μ-CT). Likewise, intuitive evaluation of these 3D datasets can be enhanced by recent advances in virtual reality (VR) hardware and software. Additionally, the generation, viewing, and manipulation of 3D X-ray diffraction datasets, such as pole figures employed for texture analysis, can also benefit from these advanced visualization techniques. We present newly-developed protocols for porting 3D data (as TIFF-stacks) into a Unity gaming software platform so that data may be toured, manipulated, and evaluated within a more-intuitive VR environment through the use of game-like controls and 3D headsets. We demonstrate this capability by rendering μ-CT data of a polymer dogbone test bar at various stages of in situ mechanical strain. An additional experiment is presented showing 3D XRD data collected on an aluminum test block with vias. These 3D XRD data for texture analysis (χ, ϕ, 2θ dimensions) enables the viewer to visually inspect 3D pole figures and detect the presence or absence of in-plane residual macrostrain. These two examples serve to illustrate the benefits of this new methodology for multidimensional analysis.

In this paper, we will report about the implementation of the self-consistent Kröner–Eshelby model for the calculation of X-ray elastic constants for general, triclinic crystal symmetry. With applying appropriate symmetry relations, the point groups of higher crystal symmetries are covered as well. This simplifies the implementation effort to cover the calculations for any crystal symmetry. In the literature, several models can be found to estimate the polycrystalline elastic properties from single crystal elastic constants. In general, this is an intermediate step toward the calculation of the polycrystalline response to different techniques using X-rays, neutrons, or ultrasonic waves. In the case of X-ray residual stress analysis, the final goal is the calculation of X-ray Elastic constants. Contrary to the models of Reuss, Voigt, and Hill, the Kröner–Eshelby model has the benefit that, because of the implementation of the Eshelby inclusion model, it can be expanded to cover more complicated systems that exhibit multiple phases, inclusions or pores and that these can be optionally combined with a polycrystalline matrix that is anisotropic, i.e., contains texture. We will discuss a recent theoretical development where the approaches of calculating bounds of Reuss and Voigt, the tighter bounds of Hashin–Shtrikman and Dederichs–Zeller are brought together in one unifying model that converges to the self-consistent solution of Kröner–Eshelby. For the implementation of the Kröner–Eshelby model the well-known Voigt notation is adopted. The 4-rank tensor operations have been rewritten into 2-rank matrix operations. The practical difficulties of the Voigt notation, as usually concealed in the scientific literature, will be discussed. Last, we will show a practical X-ray example in which the various models are applied and compared.

The growing interest in the use of powder X-ray diffractometry for materials’ characterization has led to the introduction of relevant concepts (e.g. microstructure, strain, anisotropy, texture) to undergraduate teaching in engineering and science. In this concern, the study of polycrystalline materials underlays the use of appropriate software: free, licensed, proprietary, or commercial to assist research on structure determination, structure refinement, and microstructure characterization. Today with the easy access to personal computers, routines for powder diffractometry also becomes feasible to use for non-specialist. Therefore, it would be relevant that students with computing knowledge may decide to improve routines on such three tasks incorporating their own computational approaches. In this study, we show the development of a ready-to-use and open source program written in GNU-Octave (v4.2.1) focused on X-ray diffraction line-profile analysis. The programing language platform was chosen mainly because of two reasons: (1) there is no requirement for commercial licenses, meaning that both programing language and routines can be downloaded online, facilitating collaborative efforts between students, instructors, and developers, and (2) easy re-coding of evaluation strategies is always allowed through fast implementation of modules into the code. The code, IndexCub, features routines for background subtraction, whole profile smoothing, and Kα2 radiation removal, location of diffraction peaks positions, indexing for cubic specimens, multi peak separation of individual peaks, and evaluation of full-width at half-maximum and integral breadth values. Microstructure properties are characterized through the use of integral breadth methods (e.g. Williamson–Hall) and Fourier analysis (e.g. Warren–Averbach), and the anisotropy effects are incorporated introducing calculations of contrast factors. In terms of diffraction domain sizes, size distribution, and the lattice microstrain, the analysis of the microstructure is discussed along with examples for polycrystalline coarse-grained materials (NaCl), epitaxial film (Si), and thin-films (Au) specimens. The code facilitates the understanding of microstructure analysis by using theoretical approaches well established and in state-steady level.

Powder X-ray diffraction was used to monitor the solvent-free synthesis of two-dimensional (2D) metal–organic frameworks (MOFs) via mechanochemical methods. For four isophthalic acid-based, alkoxide-functionalized organic ligands, optimal milling times were found to vary from 12 to 48 min. This work confirms that mechanochemical synthesis routes can be utilized to afford highly-crystalline, 2D MOFs.

Variation of structural parameters of dimethylammonium manganese formate [(CH3)2NH2]Mn[(HCOO)3] upon substitution by the transition elements Zn, Co, and Ni is studied by powder X-ray diffraction (PXRD) technique. These metal–organic framework (MOF) crystals were grown by solvothermal method. The PXRD patterns of all MOFs exhibited rhombohedral structure. PXRD patterns of MOFs were analyzed using Rietveld refinement method. While the parent Mn-MOF and Mn0.9Zn0.1MOF are found to have similar structural parameters, Co and Ni substituted Mn-MOFs have smaller structural parameters than that of parent Mn-MOF. The reason for this variation in the lattice parameters is explained based on the Shannon ionic radii.

A collection of 65 formulated tablets and capsules were analyzed for phase composition by full pattern matching powder diffraction methods. The collection contained 32 of the top 200 prescription drugs sold in 2016 as well as many high-volume prescriptions and over the counter drugs from prior years. The study was used to evaluate new methods of analysis as well as the efficacy of programs designed to collect references on high volume excipients and pharmaceuticals for inclusion in the Powder Diffraction File™. The use of full pattern matching methods as well as reference pattern additions of many common excipients enabled major phase excipient identification in all formulations. This included identification of crystalline, nanocrystalline, and amorphous ingredients because full pattern matching involved the use of characteristic coherent and incoherent scatter. Oftentimes identification of the major excipients significantly aided the clean identification of the active pharmaceutical ingredients (APIs) and their polymorphic form, even at low concentrations (1–10 wt. %). Overall 93% of the APIs were identified, most through a PDF® material reference, but also through patent cross-referencing and similarity analysis comparisons.

Changes of structural properties of tobermorite in autoclaved aerated concrete (AAC) for various compositions were characterized and the disadvantages of SEM analysis in this context are discussed. The influence of variations in the chemical composition of raw materials on lattice parameters, morphology and domain sizes of tobermorite was investigated by XRD and for comparison by SEM analysis. Particularly the effect of substitution by Al3+ and (SO4)2− in tobermorite structure was examined. The dimensions of coherently scattering domains were calculated based on the refinement of anisotropic peak broadening of tobermorite in XRD diffractograms using a Rietveld compatible approach. No effect of (SO4)2− on the domain sizes and lattice parameters of tobermorite could be observed. The amount of anhydrite detected by quantitative XRD analysis indicates that all of the available (SO4)2− is present as anhydrite. Lath-like shapes of domains and a larger c parameter are calculated whenever Al3+ is incorporated in a considerable amount. Formation of katoite can be observed very clearly in SEM micrographs whenever the amount of available Al3+ exceeds a distinct value in the dry mix. The effect of Al3+ and (SO4)2− on tobermorite morphology could not be observed clearly by SEM analysis in AAC samples.

Crystal structure analysis of a pyrazole carboxylic acid derivative, 5-(trifluoromethyl)-1-phenyl-1H-pyrazole-4-carboxylic acid (1) has been carried out from laboratory powder X-ray diffraction data. The crystal packing in the pyrazole carboxylic acid derivative exhibits an interplay of strong O–H…O, C–H…N and C–H…F hydrogen bonds to generate a three-dimensional molecular packing via the formation of R22(8) and R22(9) rings. Molecular electrostatic potential calculations indicated that carbonyl oxygen, pyrazole nitrogen and fluorine atoms to be the strongest acceptors. The relative contribution of different interactions to the Hirshfeld surface of pyrazole carboxylic acid and a few related structures retrieved from CSD indicates that H…H, N…H and O…H interactions can account for almost 70% of the Hirsfeld surface area in these compounds.

A total of 77 pottery shards originating from the Middle Jomon period (2500–1500 BC) were excavated from the Hinoki site in Tochigi, Japan. Fifty-five of those were Atamadai type pottery, which might contain some temper fragments from the manufacturing process. The pottery shards were analyzed by X-ray diffractometry (XRD). The mineral analyses were compared with the river sands around Mt. Tsukuba to demonstrate the temper's origin of the Atamadai type pottery. Their XRD profiles revealed the following solid solutions which could be fingerprint minerals: biotite for the temper and plagioclase, and hornblende for the clay and temper. These minerals might indicate the origin of each sample because their d-spacings depended on the solid solution composition reflecting their geological characteristics.

Advances in instrumentation, software applications, and database content have all contributed to improvements in pharmaceutical analyses by powder diffraction methods in the 21st century. When compared to the globally harmonized United States Pharmacopeia General Chapter <941>, “Characterization of Crystalline and Partially Crystalline Solids by X-ray Powder Diffraction”, many historic problems in pharmaceutical analysis have been addressed by combinations of improved methods and instrumentation. Major changes in the last 20 years include (i) a dramatic lowering in detection capability and detection limits, (ii) enhanced capabilities for dynamic measurements such as in situ analyses under a variety of conditions, and (iii) the ability to identify and characterize nanomaterials, non-crystalline, and amorphous materials by both coherent and incoherent scattering profiles.

The General Structure Analysis System (GSAS-II) package provides materials and crystallographic analysis for all types of diffraction data. It was initially made available with very limited capabilities, but over much of the last decade the features have been expanded, so that GSAS-II is now a comprehensive tool for nearly all types of structural and materials characterization studies. The need to provide materials to teach use of GSAS-II, while the software has been undergoing constant revision and expansion, has required new approaches for documentation. This has included providing tutorials, as each major new capability has been added, and context-sensitive help for each section of the program. Comments in the code are also expanded into a software reference guide. Most recently, video versions of more than half of the tutorials were created and others were provided with animated graphics. All GSAS-II documentation is web-based.

The crystal structure of bumetanide has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Bumetanide crystallizes in space group P-1 (#2) with a = 5.00168(4), b = 9.22649(3), c = 19.59924(14) Å, α = 80.7941(5), β = 82.8401(7), γ = 86.8148(7)°, V = 885.268(9) Å3, and Z = 2. The crystal structure is layered with the double layers parallel to the ab plane. The exterior of the layer is composed of hydrocarbon portions of the molecule, both phenyl rings and butyl side chains. The central portion of the bilayer contains the hydrogen-bonding regions, both the carboxylic acid dimers and the hydrogen bonds involving the sulfonamide groups. The molecular conformations of bumetanide in this current triclinic structure and the previously-determined monoclinic polymorph FEDGON are very similar, as are the energies of the two polymorphs. The powder pattern is included in the Powder Diffraction File™ as entry 00-066-1609.

We report on the X-ray diffraction data and unit-cell parameters of Mn4C, which has a cubic perovskite-type structure with a = 3.8726 Å and unit-cell volume V = 58.1 Å3. The measured lines were indexed and are consistent with the space group $ Pm { \bar {\it 3}} m$ (No. 221).

Advanced courses in Applied Crystallography for Nanosciences are not often delivered in Academia and, consequently, require the organization of events specifically tailored to PhD students, postdocs, and young researchers at the very beginning of their scientific careers.