Upgrade of crystallography beamline BL19U1 at the Shanghai Synchrotron Radiation Facility

The protein complex crystallography beamline BL19U1 is preparing for the establishment of an automated drug screening platform by upgrading both hardware and data collection control systems to optimize efficiency. The upgrade of the experimental station devices and data collection control system on the BL19U1 beamline are reported in this paper.

Applications of the Clifford torus to material textures

A new 2D representation of 3D material textures based on the Clifford torus is presented.

Ray-tracing analytical absorption correction for X-ray crystallography based on tomographic reconstructions

A tomography-based ray-tracing approach for analytical absorption corrections for X-ray crystallography is presented. Several examples from long-wavelength macromolecular crystallography experiments demonstrate the efficacy of this new method.

Energy storage properties influenced by relaxor ferroelectric properties dependent on the growth direction of epitaxial Bi₂SiO₅ thin films

Bi₂SiO₅ thin films on Nb-doped (111), (110) and (111) SrTiO₃ substrates exhibit ferroelectric and energy storage characteristics influenced by their various crystallinities.

Coupling between cation and anion disorder in β-K₂Ca₃(CO₃)₄

This report describes an `order–disorder' transition in the recently discovered K₂Ca₃(CO₃)₄ material and the disordered β modification with an unusual K–Ca isomorphism in cation sites. The appearance of mixed K/Ca sites, in turn, causes strong orientational disorder of anions and the emergence of an inversion center (the ordered α modification is non-centrosymmetric).

Bragg Spot Finder (BSF): a new machine-learning-aided approach to deal with spot finding for rapidly filtering diffraction pattern images

Bragg Spot Finder (BSF) is a U-Net-based spotfinder with image preprocessing, a U-Net segmentation backbone, and post-processing that includes artifact removal and watershed segmentation. BSF is supported by the Bragg Spot Detection (BSD) benchmark image dataset containing more than 300 images with more than 66 000 spots.

High-pressure intrusion of double salt aqueous solution in pure silica chabazite: searching for cation selectivity

The intrusion of a ternary electrolyte solution (KCl + CaCl₂) in pure silica chabazite is studied. The structural investigations reveal that the composition of the intruded species is different from those of the initial solution and that the K cations are separated from the Ca cations at the beginning of the intrusion. This seems to be due to different mechanisms of desolvation.

Novel high-efficiency 2D position-sensitive ZnS:Ag/⁶LiF scintillator detector for neutron diffraction

A novel high-efficiency 2D position-sensitive wavelength-shifting-fibre ZnS:Ag/⁶LiF scintillator detector has been developed at ISIS for single-crystal diffraction applications. More than a factor of 3 improvement in efficiency was achieved with this detector compared with clear-fibre scintillator detectors, and software routines for further optimizations in position sensitivity and uniformity have been implemented.

The tin content of lead inclusions in ancient tin-bronze artifacts: a time-dependent process?

The disequilibrium Sn content in Pb inclusions present in ancient (Sn,Cu)-bronze samples may in principle be used for authentication purposes. The present article explores the applicability of a method based on precise diffraction measurement of the Pb lattice parameter.

Phase-contrast neutron imaging compared with wave propagation and McStas simulations

This article discusses the phase-contrast effect and compares two simulation methods based on different theoretical frameworks. It demonstrates the ability to reproduce the phase effect in experimental data, using the well known simulation framework McStas [Willendrup & Lefmann (2020). J. Neutron Res. 22, 1–16].

Reconstructing the reflectivity of liquid surfaces from grazing incidence X-ray off-specular scattering data

Reflectivity from liquid surfaces can be accurately obtained from the diffuse scattering signal around the specular reflection measured by grazing incidence off-specular scattering experiments along with the capillary wave model of diffuse scattering. This method allows for a much faster reflectivity profile acquisition with an improved signal–noise ratio compared with conventional specular reflectometry.

Low-background ultrahigh-purity aluminium window for small-angle neutron scattering using monochromatic cold neutrons

An ultrahigh-purity aluminium (>99.999%) window that can generate much lower small-angle neutron scattering than conventional aluminium alloys and has a fracture toughness much higher than monocrystalline silicon was implemented as the 500 mm-diameter neutron window in SANS-J at JRR-3, Japan.

Application of laboratory micro X-ray fluorescence devices for X-ray topography

A laboratory X-ray topography technique is presented. One of the advantages of this technique is that it can be used to visualize dislocations in non-polished and non-planar crystals with a very pronounced surface profile.

Design and fabrication of 3D-printed in situ crystallization plates for probing microcrystals in an external electric field

A 3D-printed in situ crystallization plate is presented, which can be used to probe protein microcrystals in an external electric field.

Multifitting 2: software for reflectometric, off-specular and grazing-incidence small-angle scattering analysis of multilayer nanofilms

A computer program called Multifitting, which was developed to model the optical properties of multilayer films over a wide range of wavelengths, is described here. Its key features are the ability to work simultaneously with an arbitrary number of reflectometric and scatterometric experimental curves, and an ergonomic graphical user interface that is designed for intensive daily use in the characterization of thin films.

iModel: an interactive 3D crystal structure visualization program

iModel is a 3D crystal structure visualization program that allows users to manipulate and customize models. Developed using LabVIEW and Python, it is a potentially powerful tool for crystal structure visualization.

Program VUE: analysing distributions of cryo-EM projections using uniform spherical grids

The program VUE analyses the distribution of 2D projections in cryo-EM and presents this information in a quantitatively exact manner via maps and other diagrams.

The pypadf package: computing the pair angle distribution function from fluctuation scattering data

A Python-based software package is presented that can compute the pair angle distribution function from X-ray or electron fluctuation scattering data of disordered materials.

MatchMaps: non-isomorphous difference maps for X-ray crystallography

MatchMaps is a generalization of the isomorphous difference map allowing for computation of difference maps between poorly isomorphous and non-isomorphous pairs of crystallographic data sets. MatchMaps is implemented as a simple-to-use Python-based command-line interface.