Extraction of plutonium-containing microcrystals from Hanford soil using a focused ion beam for single-crystal X-ray diffraction analysis

Focused ion beam/scanning electron microscope (FIB/SEM) techniques have been used to identify and extract single microcrystals of plutonium species from radioactive soil taken from the Z-9 waste crib at the Hanford Site. Using the FIB/SEM, plutonium-containing microcrystals as small as 28 µm³ were prepared for single-crystal X-ray diffraction and characterized using a laboratory-based diffractometer.

Molecular dynamics simulation of organic crystals: introducing the CLP-dyncry environment

A proof of concept is given for CLP-dyncry, a free molecular dynamics tool designed for the reliable simulation of organic molecules in condensed phase.

A simultaneous X-ray diffraction–differential scanning calorimetry study into the phase transitions of mefenamic acid

The phase transitions of mefenamic acid have been studied by synchrotron X-ray powder diffraction combined with differential scanning calorimetry. A direct transition from form I to forms II and III was noted during heating, with the possible observation of a new and as-yet unidentified polymorph at elevated temperatures.

Assessment of phase transition and thermal expansion coefficients by means of secondary multiple reflections of Renninger scans

Structural phase transitions have been evaluated and thermal expansion coefficients determined using Renninger scan patterns. The findings were determined by choosing the primary and secondary reflections appropriately, and by monitoring the secondary peak positions in X-ray multiple diffraction patterns.

High-viscosity sample-injection device for serial femtosecond crystallography at atmospheric pressure

A high-viscosity cartridge-type injector for serial femtosecond crystallography has been developed at SPring-8 Angstrom Compact Free-Electron Laser.

The dynamical theory of diffraction in a crystal modulated by a surface acoustic wave in the case of spatially restricted X-ray beams

The dynamical theory of X-ray diffraction in a crystal modulated by a surface acoustic wave has been developed for spatially restricted beams. This approach allows one to calculate reciprocal-space maps and their vertical and lateral cross sections.

Full-field neutron microscopy based on refractive optics

A theoretical description is provided of full-field neutron microscopy based on refractive optics. The potential use is illustrated by comparison with the state of the art within bright-field microscopy, small-angle neutron scattering microscopy, mapping of grains and stresses, and confocal microscopy.

Simultaneous X-ray radiography and diffraction topography imaging applied to silicon for defect analysis during melting and crystallization

A setup for simultaneous time-resolved X-ray radiography and diffraction topography imaging is presented. It is used to study defect generation and growth mechanisms during heating, solidification and cooling of a silicon crystal.

X-ray back-diffraction: can we further increase the energy resolution by tuning the energy slightly below that of exact backscattering?

X-ray back-diffraction (XBD) corresponding to the condition where the energy can be tuned slightly below that of exact backscattering (labeled residual XBD) has been characterized to check whether under this extreme condition the energy resolution can be further improved.

An iterative reconstruction algorithm for pole figure inversion using total variation regularization

A new pole figure inversion technique using the `cubochoric' and modified-Lambert projection methods together with total variation regularization is proposed.

Fast fitting of reflectivity data of growing thin films using neural networks

Artificial neural networks trained with simulated data are shown to correctly and quickly determine film parameters from experimental X-ray reflectivity curves.

Small-angle X-ray scattering intensity of multiscale models of spheres

Methods for computing small-angle scattering intensity for Boolean models of spheres from known covariance or from projection of realizations are reviewed and compared.

Qu­antification of amorphous siliceous fly ash in hydrated blended cement pastes by X-ray powder diffraction

A step-by-step protocol for the quantification of amorphous siliceous fly ash in hydrated cement using X-ray powder diffraction, based on the Rietveld PONKCS (partial or no known crystal structure) method, is presented. The results show good accuracy in terms of quantification by comparison against independent measurements.

α-Nickel sulfate hexahydrate crystals: relationship of growth conditions, crystal structure and properties

Single-crystal neutron diffraction, Raman, thermogravimetric and microhardness studies are performed on two α-nickel sulfate hexahydrate crystals grown under different conditions. The relation between the growth conditions, crystal structure and crystal properties is elucidated.

Formation of two crystal modifications of Fe₇C_3−x at 5.5 GPa

Experiments on diamond synthesis in the Fe–C system at 5.5 GPa and 1623 K were performed. X-ray diffraction analysis showed the formation of two carbides, Fe₃C and Fe₇C₃. Two polytypic modifications of Fe₇C₃ are described, namely Fe₁₄C₆ and Fe₂₈C_12−x.

Successful sample preparation for serial crystallography experiments

Some ideas and methods on how to produce high-quality samples for successful serial crystallography experiments are presented. The methods here described are aimed at experimenters trying to convert their vapour diffusion crystallization conditions into large-scale batch micro-crystallization.

Depicting the crystal structure of fibrous ferrierite from British Columbia using a combined synchrotron techniques approach

By combining nano-diffraction single-crystal data and tomography data (collected at ESRF), a Rietveld refinement has been improved so as to obtain a reliable crystal model of a fibrous ferrierite.

Multireflection grazing-incidence X-ray diffraction: a new approach to experimental data analysis

New methods of linear regression are used for multireflection grazing-incidence X-ray diffraction data analysis with correct elastic anisotropy prediction.

MRPC (Missing Regions in Polypeptide Chains): a knowledgebase

An interactive database has been created for identifying the missing regions in all the protein structures available in the Protein Data Bank.

PSX, Protein–Solvent Exchange: software for calculation of deuterium-exchange effects in small-angle neutron scattering measurements from protein coordinates

Using established models, the effect of exposing protonated protein samples to D₂O is calculated, and the impact on small-angle neutron scattering experiments is assessed. Software to evaluate the effect of this from a given structure is introduced, and examples of applications are given.

FXD-CSD-GUI: a graphical user interface for the X-ray-diffraction-based determination of crystallite size distributions

A graphical interface to the Python module fxdcsd, which analyses crystallite size distributions via Bragg intensities measured with two-dimensional detectors, is described.

DatView: a graphical user interface for visualizing and querying large data sets in serial femtosecond crystallography

DatView is a new graphical user interface for simplifying analysis by facilitating plotting parameters and exporting selections from large serial crystallography data sets.

CrysX: crystallographic tools for the Android platform

CrysX is a user-friendly suite of Android apps for crystallographic studies. Key features include 3D visualization/modelling of structures, diffraction pattern simulation and analysis, equation of state calculations, and augmented reality visualization of structures.

Graphical user interface for the program FraGen

A Python graphical user interface (GUI) has been designed for FraGen, a real-space structure determination program. With this GUI, users can prepare input files for FraGen easily, and visually check, evaluate and screen the resulting structure models saved in the output files generated by FraGen.

Direct protein crystallization on ultrathin membranes for diffraction measurements at X-ray free-electron lasers. Corrigendum

Errors in the article by Opara, Martiel, Arnold, Braun, Stahlberg, Makita, David & Padeste [J. Appl. Cryst. (2017), 50, 909–918] are corrected.

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