Laboratory X-ray Diffractometer Research Articles

Orientational and crystallographic relationships in thin films of yttrium orthoferrite on sapphire substrates.

An algorithm is proposed for determining the orientational relationships and crystal unit-cell parameters of thin films using a laboratory X-ray diffractometer and stereographic projections. It is illustrated by the treatment of experimental data obtained for yttrium orthoferrite YFeO3 films on single crystalline sapphire (Al2O3) substrates for film thicknesses in the range from 100 to 7000 Å. Precise determination of unit-cell constants and angles is possible by combining the results of X-ray measurements made in the in-plane and out-of-plane geometries. The unit-cell unit parameters and orientation relationships for thin films were determined. For the studied films, typical errors in determining unit-cell parameters and angles are better than 0.17 Å and 0.17°, respectively.

Battery Thermalization for Operando Synchrotron Powder Diffraction: Application to the Ca-TiS2 System

Characterizing electrode materials and understanding its behavior during redox process is a key factor for battery improvement. In Situ techniques on Operando batteries are of particular interest since they do not only probe the material during the electrochemical process but avoid its hazardous and tedious extraction and transfer under inert atmosphere from an electrochemical cell to e.g. capillaries, to perform Ex Situ data collection. Synchrotron based techniques –absorption and diffraction – together with improved detectors, are now intensively used in such In Situ studies on Operando batteries since they allow fast and real time data acquisition during the electrochemical, ion (des-)insertion, process. So far most In Situ X-ray powder diffraction studies on Operando batteries are performed at room temperature using either coin cells or so called Leriche cells [1] (pouch cells, despite widely used for spectroscopy, are generally not favored for diffraction since the container material produce additional Bragg peaks). At ALBA we slightly modified both types of cells: Leriche type and more widespread used CR2032-type coin cells so as to perform data collection in temperature range -10° – 100° C. (see picture)Both types of cell have been used to study the intercalation of calcium in TiS2, previously determined by Ex Situ powder diffraction [2]. We managed to collect powder patterns operando at 60°C, 45°C and room temperature. (Des-)Insertion of solvated Ca2+ in TiS2 was favoured by temperature, its signature being the appearance of a new phase with a first diffraction peak at very low angles (~17.7 Å in terms of d-spacing). The process was found to be solvent dependent and reversible upon oxidation, which differs from Li cells where a similar process was observed.[3]Either of these thermalized cells can be used at CELLS-ALBA synchrotron for Power Diffraction on BL04-MSPD beamline or hard X-ray Absorption Spectroscopy (XANES/EXAFS) on BL22-CLEASS, and since 2023 also using simultaneous Powder Diffraction and hard X-ray Absorption Spectroscopy in BL16-NOTOS beamline. Moreover, the Leriche setup is also designed to fit for a use in laboratory X-ray diffractometers, in both reflection and transmission. Leriche et al. (2010). J. Electrochem. Soc., 157(5), A606-A610.Tchitchekova et al (2018). Chem. Mater 30, 847−856Houdeville et al. (2021). J. Electrochem. Soc., 168, 030514 Figure 1

Semi-Quantitative Analyses of Ferromanganese Nodules from the Pacific Ocean Using Synchrotron X-ray Powder Diffraction

The geochemistry and mineralogy of Mn nodules offer crucial insights into the origins, environmental changes, and distribution of abyssal resources. However, the conventional laboratory X-ray diffractometer, usually employed for semi-quantitative analysis of mineral composition in Mn nodules, often fails to sufficiently detect minor phases due to beam flux limitations and high background signals. In this study, we investigated differences in manganate composition, even when comprising around 1% of the phase fraction, in two manganese nodules (KC-8 and KODOS-10) using high-resolution synchrotron X-ray diffraction. The Mn/Fe ratios of KC-8 and KODOS-10 were 1.32 and 6.24, respectively, indicating that KC-8 and KODOS-10 were predominantly formed in hydrogenetic and diagenetic environments. Both samples contained quartz, vernadite, buserite, and feldspar. Todorokite and illite were exclusively observed in KODOS-10. In KC-8, the phase fractions of vernadite and buserite among manganates ranged from 94(5)%–100(4)% and 6(1)%–0%, respectively. However, in KODOS-10, the fractions of vernadite, buserite, and todorokite ranged from 47(1)%–56(2)%, 33.6(4)%–40.1(3)%, and 10(3)%–16.3(8)%, respectively.

Preparation and Crystallographic Analysis of a Complex of SARS-CoV-2 S-Protein Receptor-Binding Domain with a Virus-Neutralizing Nanoantibody

Coronavirus SARS-CoV-2 was the cause of global pandemic COVID-19 that has claimed millions of lives around the world. One of the approaches to the therapy of severe forms of COVID-19 is based on the use of virus-neutralizing antibodies against the receptor-binding domain (RBD) of the virus spike glycoprotein (S). Detailed structural data on particular epitopes recognized by these virus-neutralizing antibodies is an important aspect of the improvement of available antibodies in order to extend the range of recognized virus strains. A stoichiometric complex of the virus-neutralizing single-domain antibody P2C5 and the glycosylated form of SARS-CoV-2 S protein RBD was obtained. Despite numerous conditions in which the crystal growth of the complex was observed, these crystals showed poor diffraction, apparently because of heterogeneity associated with the glycosylation of RBD. With the aim of improving the crystal quality, deglycosylase PNGase F was produced in a bacterial expression system and deglycosylation of RBD was performed. Despite low solubility of the deglycosylated form of RBD, it retains the ability to bind to the nanoantibody P2C5, resulting in the formation of a stable heterodimeric complex during gel filtration. The crystals of this complex were obtained. They showed diffraction to a similar resolution of ~4 Å on a laboratory X-ray diffractometer and at a synchrotron radiation source. The symmetry space group, the unit cell parameters of the crystal, and its protein composition were determined.

Comparative study of conventional and synchrotron X-ray electron densities on molecular crystals.

Five different electron density datasets obtained from conventional and synchrotron single crystal X-ray diffraction experiments are compared. The general aim of the study is to investigate the quality of data for electron density analysis from current state-of-the-art conventional sources, and to see how the data perform in comparison with high-quality synchrotron data. A molecular crystal of melamine was selected as the test compound due to its ability to form excellent single crystals, the light atom content, and an advantageous suitability factor of 3.6 for electron density modeling. These features make melamine an optimal system for conventional X-ray diffractometers since the inherent advantages of synchrotron sources such as short wavelength and high intensity are less critical in this case. Data were obtained at 100 K from new in-house diffractometers Rigaku Synergy-S (Mo and Ag source, HyPix100 detector) and Stoe Stadivari (Mo source, EIGER2 1M CdTe detector), and an older Oxford Diffraction Supernova (Mo source, Atlas CCD detector). The synchrotron data were obtained at 25 K from BL02B1 beamline at SPring-8 in Japan (λ = 0.2480 Å, Pilatus3 X 1M CdTe detector). The five datasets were compared on general quality parameters such as resolution, ⟨I/σ⟩, redundancy and R factors, as well as the more model specific fractal dimension plot and residual density maps. Comparison of the extracted electron densities reveals that all datasets can provide reliable multipole models, which overall convey similar chemical information. However, the new laboratory X-ray diffractometers with advanced pixel detector technology clearly measure data with significantly less noise and much higher reliability giving densities of higher quality, compared to the older instrument. The synchrotron data have higher resolution and lower measurement temperature, and they allow for finer details to be modeled (e.g. hydrogen κ parameters).

Synchrotron X-ray Studies of the Structural and Functional Hierarchies in Mineralised Human Dental Enamel: A State-of-the-Art Review.

Hard dental tissues possess a complex hierarchical structure that is particularly evident in enamel, the most mineralised substance in the human body. Its complex and interlinked organisation at the Ångstrom (crystal lattice), nano-, micro-, and macro-scales is the result of evolutionary optimisation for mechanical and functional performance: hardness and stiffness, fracture toughness, thermal, and chemical resistance. Understanding the physical-chemical-structural relationships at each scale requires the application of appropriately sensitive and resolving probes. Synchrotron X-ray techniques offer the possibility to progress significantly beyond the capabilities of conventional laboratory instruments, i.e., X-ray diffractometers, and electron and atomic force microscopes. The last few decades have witnessed the accumulation of results obtained from X-ray scattering (diffraction), spectroscopy (including polarisation analysis), and imaging (including ptychography and tomography). The current article presents a multi-disciplinary review of nearly 40 years of discoveries and advancements, primarily pertaining to the study of enamel and its demineralisation (caries), but also linked to the investigations of other mineralised tissues such as dentine, bone, etc. The modelling approaches informed by these observations are also overviewed. The strategic aim of the present review was to identify and evaluate prospective avenues for analysing dental tissues and developing treatments and prophylaxis for improved dental health.

Rapid non-mechanical reciprocal space mapping using LiNbO3-based bimorph piezoactuator

A new approach is proposed for fast recording Reciprocal Space Maps (RSM) of crystals without using mechanical systems. It is based on the simultaneous use of two Adaptive Bending X-ray Optics (ABXO) elements made of lithium niobate crystals located on a laboratory X-ray diffractometer at the positions of the monochromator and analyzer. The technique has been tested on a model silicon crystal. It was shown that the proposed technique allows fast and precision measurements of the RSM, providing significant progress both in speed (up to 30 times) and accuracy of the data (up to 3 times) obtained. It opens up opportunities for studying the evolution of the defective structure of various prospective crystalline materials under external loading.

A multipurpose laboratory diffractometer for operando powder X-ray diffraction investigations of energy materials.

Laboratory X-ray diffractometers are among the most widespread instruments in research laboratories around the world and are commercially available in different configurations and setups from various manufacturers. Advances in detector technology and X-ray sources push the data quality of in-house diffractometers and enable the collection of time-resolved scattering data during operando experiments. Here, the design and installation of a custom-built multipurpose laboratory diffractometer for the crystallographic characterization of battery materials are reported. The instrument is based on a Huber six-circle diffractometer equipped with a molybdenum microfocus rotating anode with 2D collimated parallel-beam X-ray optics and an optional two-bounce crystal monochromator. Scattered X-rays are detected with a hybrid single-photon-counting area detector (PILATUS 300K-W). An overview of the different diffraction setups together with the main features of the beam characteristics is given. Example case studies illustrate the flexibility of the research instrument for time-resolved operando powder X-ray diffraction experiments as well as the possibility to collect higher-resolution data suitable for diffraction line-profile analysis.

Three-dimensional curving of crystal planes in wide bandgap semiconductor wafers visualized using a laboratory X-ray diffractometer

The curving of crystal planes (CCP) in wide bandgap semiconductor wafers, caused by thermal stress during crystal growth or wafer planarization processes, poses serious problems in subsequent epitaxial growth and device fabrication; therefore, it requires a precise assessment. In this paper, we report a method for visualizing the CCP in three-dimensional space using a laboratory X-ray diffractometer. The characteristic CCP is presented for 4H-SiC, GaN, AlN, and β-Ga2O3 commercial substrates with widely varied size and thickness, surface orientation, surface treatment, dopant species, and dislocation density. The results will aid crystal growers in gaining an overview regarding the shape of the CCP (e.g., convex or concave, isotropic or anisotropic) and the radius of curvature in these up-to-date power semiconductor wafers. The method can be used to optimize crystal growth conditions and wafer planarization processes.

Detection and Analysis of Drug Crystals in Medical Transdermal Patches by Using X-ray Diffraction Measurement

The crystallization of active pharmaceutical ingredients (APIs) in matrix-type transdermal patches has implications for the rate of drug absorption through the skin and patch adhesion strength. Therefore, the presence or absence and the degree of API crystallinity must be controlled to guarantee the quality of patches. In this study, the utility of laboratory-level X-ray diffractometers for the detection and analysis of crystalline APIs in transdermal patches was investigated using medical patches of tulobuterol and isosorbide dinitrate. Several matrix-type patches employ a controlled drug delivery system containing intentionally crystallized API. Both benchtop and high-resolution laboratory X-ray diffractometers can detect several characteristic peaks of the APIs in these patches even if the patches are wrapped in an outer bag, although a benchtop model provides peak heights one-seventh to one-fifth that of a high-resolution instrument. An isosorbide dinitrate patch containing an unintentionally crystallized spot was wrapped in an outer bag, followed by measurements using both X-ray diffractometers. For both instruments, several isosorbide dinitrate-derived peaks were detected only at the crystallized spot, although the signal-to-noise ratio was poorer for the benchtop model. These results show that a high-resolution X-ray diffractometer is advantageous for high-detection sensitivity and offers a high degree of freedom of the measurement position on the sample. It was concluded that a laboratory-level high-resolution X-ray diffractometer can be used to examine the crystalline state of APIs in patches inside an unopened outer bag.

Multipurpose diffractometer for in situ X-ray crystallography of functional materials

Laboratory X-ray diffractometers play a crucial role in X-ray crystallography and materials science. Such instruments still vastly outnumber synchrotron facilities and are responsible for most of the X-ray characterization of materials around the world. The efforts to enhance the design and performance of in-house X-ray diffraction instruments benefit a broad research community. Here, the realization of a custom-built multipurpose four-circle diffractometer in the laboratory for X-ray crystallography of functional materials at Tel Aviv University, Israel, is reported. The instrument is equipped with a microfocus Cu-based X-ray source, collimating X-ray optics, four-bounce monochromator, four-circle goniometer, large (PILATUS3 R 1M) pixel area detector, analyser crystal and scintillating counter. It is suitable for a broad range of tasks in X-ray crystallography/structure analysis and materials science. All the relevant X-ray beam parameters (total flux, flux density, beam divergence, monochromaticity) are reported and several applications such as determination of the crystal orientation matrix and high-resolution reciprocal-space mapping are demonstrated. The diffractometer is suitable for measuring X-ray diffraction in situ under an external electric field, as demonstrated by the measurement of electric-field-dependent rocking curves of a quartz single crystal. The diffractometer can be used as an independent research instrument, but also as a training platform and for preparation for synchrotron experiments.

Operando SAXS study of a Pt/C fuel cell catalyst with an X-ray laboratory source

Small-angle X-ray scattering (SAXS) is a powerful technique to investigate the degradation of catalyst materials. Ideally such investigations are performed operando, i.e. during a catalytic reaction. An example of operando measurements is to observe the degradation of fuel cell catalysts during an accelerated stress test (AST). Fuel cell catalysts consist of Pt or Pt alloy nanoparticles (NPs) supported on a high surface area carbon. A key challenge of operando SAXS measurements is a proper background subtraction of the carbon support to extract the information of the size distribution of the Pt NPs as a function of the AST treatment. Typically, such operando studies require the use of synchrotron facilities. The background measurement can then be performed by anomalous SAXS or in a grazing incidence configuration. In this work we present a proof-of-concept study demonstrating the use of a laboratory X-ray diffractometer for operando SAXS. Data acquisition of operando SAXS with a laboratory X-ray diffractometer is desirable due to the general challenging and limited accessibility of synchrotron facilities. They become even more crucial under the ongoing and foreseen restrictions related to the COVID-19 pandemic. Although, it is not the aim to completely replace synchrotron-based studies, it is shown that the background subtraction can be achieved by a simple experimental consideration in the setup that can ultimately facilitate operando SAXS measurements at a synchrotron facility.

Phase transition in an organic ferroelectric: glycinium phosphite, with and without X-ray radiation damage.

Thermal evolution of an organic ferroelectric, namely, glycinium phosphite, was probed by multi-temperature single-crystal diffraction using synchrotron radiation and also by a similar experiment with a laboratory X-ray diffractometer. Both series of measurements showed a transition from the paraelectric to the ferroelectric state at nearly the same temperature, Tc= 225 K. Temperature evolution of the unit-cell parameters and volume are drastically different for the synchrotron and laboratory data. The latter case corresponds to previous reports and shows an expected contraction of the cell on cooling. The data collected with the synchrotron beam show an abnormal nonlinear increase in volume on cooling. Structure analysis shows that this volume increase is accompanied by a suppression of scattering at high angles and an apparent increase of the anisotropic displacement parameters for all atoms; we therefore link these effects to radiation damage accumulated during consecutive data collections. The effects of radiation on the formation of the polar structure of ferroelectric glycinium phosphite is discussed together with the advantages and drawbacks of synchrotron experimentation with fine temperature sampling.

Hard x-ray methods for studying the structure of amorphous thin films and bulk glassy oxides

High-energy photon diffraction minimizes many of the corrections associated with laboratory x-ray diffractometers, and enables structure factor measurements to be made over a wide range of momentum transfers. The method edges us closer toward an ideal experiment, in which coordination numbers can be extracted without knowledge of the sample density. Three case studies are presented that demonstrate new hard x-ray methods for studying the structure of glassy and amorphous materials. First, the methodology and analysis of high-energy grazing incidence on thin films is discussed for the case of amorphous In2O3. The connectivity of irregular InO6 polyhedra are shown to exist in face-, edge- and corner-shared configurations in the approximate ratio of 1:2:3. Secondly, the technique of high-energy small and wide angle scattering has been carried out on laser heated and aerodynamically levitated samples of silica-rich barium silicate (20BaO:80SiO2), from the single phase melt at 1500 oC to the phase separated glass at room temperature. Based on Ba–O coordination numbers of 6 to 7, it is argued that the although the potential of Ba is ionic, it is weak enough to cause the liquid–liquid immiscibility to become metastable. Lastly, high-energy small and wide angle scattering has also been applied to high water content (up to 12 wt.%) samples of hydrous SiO2 glass quenched from 1500 oC at 4 GPa. An increase of Si1–O2 correlations at 4.3 Å is found to be consistent with an increase in the population of three-membered SiO4 rings at the expense of larger rings.

Design and development of a miniaturized multiaxial test setup for in situ x-ray diffraction experiments.

In this work, a novel stand-alone multi-axial loading test setup was developed to test miniature samples under uniaxial tension, uniaxial compression, in-plane biaxial tension, and biaxial compression stress states. Good agreement in stress-strain responses was observed between the uniaxial experiments carried out using the miniature sample geometry in the custom-built setup and the uniaxial standard geometry in a universal testing machine. With regard to biaxial experiments, the full-field strain captured using digital image correlation for the biaxial specimens revealed strain homogeneity in the central gage section of the sample. Furthermore, the in situ capability of the setup was demonstrated by integrating it with a commercial laboratory x-ray diffractometer, and good agreement was found between the calculated stress values from the load sensor and the stress obtained using x-ray diffraction.

Study of Short-range Ordering in Amorphous and Nanocrystalline Materials from Laboratory based Pair Distribution Function (LPDF)

Determination of local atomic structure at nanoscale for both amorphous and nanocrystalline materials is very difficult and challenging. Local arrangement of atoms needs to be studied for understanding the local or short-range structural information. Pair distribution function (PDF) analysis is a technique used to study the short-range structure of the materials based on local atomic arrangement of atoms using synchrotron and neutron sources. But there is a demand for routine analysis based on laboratory X-ray diffractometer (XRD) using Ag radiation (λ=0.5608 Å) with maximum achievable Q value of 22 Å–1. An attempt has been taken to study the short-range structure in crystalline Ni, silica glass (SiO2) and nano silica using total scattering experiment to show the capabilities and usefulness of PDF technique in laboratory XRD and are compared with the data from synchrotron radiation to achieve good quality scattering data and optimizing technical feasibility of the optics. PDF results of Ni showed the goodness of optical alignment. The first Si-O distance for both silica samples signified that they hold short- range order within the tetrahedral unit while differences are observed at higher radial distances. Laboratory based PDF experiment helped to get local/short- range structural information for better understanding the multifunctional properties of nano and disordered materials.

In situ monitoring of hydrothermal reactions by X-ray diffraction with Bragg–Brentano geometry

This note describes an autoclave chamber developed and constructed by Anton Paar and its application for in situ experiments under hydrothermal conditions. Reactions of crystalline phases can be studied by successive in situ measurements on a conventional laboratory X-ray diffractometer with Bragg-Brentano geometry at temperatures <483 K and saturated vapour pressure <2 MPa. Variations in the intensity of X-ray diffraction reflections of both reactants and products provide quantitative information for studying the reaction kinetics of both dissolution and crystal growth. Feasibility is demonstrated by studying a cementitious mixture used for autoclaved aerated concrete production. During a period of 5.7 h at 466 K and 1.35 MPa, the crystallization of torbermorite and the partial consumption of quartz were monitored.

Combined X-ray and neutron single-crystal diffraction in diamond anvil cells.

It is shown that it is possible to perform combined X-ray and neutron single-crystal studies in the same diamond anvil cell (DAC). A modified Merrill-Bassett DAC equipped with an inflatable membrane filled with He gas has been developed. It can be used on laboratory X-ray and synchrotron diffractometers as well as on neutron instruments. The data processing procedures and a joint structural refinement of the high-pressure synchrotron and neutron single-crystal data are presented and discussed for the first time.

Deriving Amorphous Component Abundance and Composition of Rocks and Sediments on Earth and Mars

AbstractX‐ray amorphous materials have been detected in all samples measured by the CheMin X‐ray diffractometer (XRD) on board the Mars Science Laboratory rover in Gale Crater, Mars. The origin(s) of these materials are poorly understood, and there are significant uncertainties on their estimated abundances and compositions. Three methods are used to estimate the bulk amorphous component abundance and composition of Martian samples using XRD and bulk chemical data: (1) Rietveld refinements, (2) FULLPAT analyses, and (3) mass balance calculations. We tested these methods against a quantitative XRD (internal standard) method commonly used in terrestrial laboratories. Additionally, we tested for instrumentation effects by measuring our samples on a laboratory XRD instrument (PANalytical X'Pert Pro) and the CheMin test bed instrument (CheMin IV). We used three natural samples known to contain amorphous materials: glacial sediment, Hawaiian soil, and a paleosol. Our methods resulted in nine amorphous abundances and four amorphous compositions for each sample. For a single sample, amorphous abundance estimates and amorphous compositions are relatively similar across all estimation methods. CheMin analog measurements perform well in our tests, with amorphous abundances and compositions comparable to laboratory quantitative XRD measurements, though slightly underestimated. This suggests that previous amorphous component estimates for Martian samples are relatively accurate. This study highlights the usefulness of the mass balance calculation method for characterizing amorphous materials in terrestrial samples, providing important supplemental information to destructive and time consuming size separation and dissolution procedures.

Characterizing proteins using SAXS on a multi-purpose laboratory X-ray diffractometer

Characterizing proteins using SAXS on a multi-purpose laboratory X-ray diffractometer