Validating classical line profile analyses using microbeam diffraction from individual dislocation cell walls and cell interiors

Depth-resolved microbeam diffraction was used to measure diffraction line profiles from numerous individual dislocation cell walls and cell interiors in a heavily deformed Cu single crystal, allowing the construction of the cell-interior and cell-wall subprofiles that have been approximated in the line profile analysis literature for the past 30 years. Comparison of the reconstructed subprofiles and the macroscopic asymmetric line profile from the same sample allows the first direct tests of many of the assumptions that have been used in such analyses.

Single-pass flow-through reaction cell for high-temperature and high-pressure in situ neutron diffraction studies of hydrothermal crystallization processes

A versatile flow-through reaction cell, featuring independent and accurate controls of temperature (up to 673 K), pressure (up to 46 MPa), fluid volume (≥65 ml) and flow rate (0.01–10 ml min⁻¹), has been developed and commissioned for in situ neutron diffraction investigation of crystallization under mild to extreme hydrothermal conditions (e.g. supercritical).

A high-resolution synchrotron powder diffraction study of substituted gallium ferrites using flat-plate fixed angle of incidence geometry on beamline I11 at Diamond

This paper outlines a data collection strategy and the necessary corrections for synchrotron powder data collected in flat-plate geometry. A number of solid solutions in multiferroic Ga_(2−x)Fe_xO₃ have been used to deliver very accurate crystal structures suitable for modelling material functionality.

Synthesis and characterization of one-dimensional vertically aligned Sb-doped ZnO nanowires

The morphology, structure and luminescence properties of one-dimensional vertically aligned Sb-doped ZnO nanowires on a silicon substrate have been studied. The results show that the use of Si(111) is a critical factor for the growth of vertically aligned nanowires.

High-pressure phase transitions and equations of state in NiSi. I. Ab initio simulations

The relative stability of high-pressure phases of NiSi has been determined by ab initio calculations. Above ∼250 GPa, NiSi adopts the CsCl structure and therefore at the pressures of the Earth's inner core it will be isostructural with FeSi.

A model for calculating diffraction elastic constants

A model is proposed to calculate the diffraction elastic constants that convert lattice strain into macroscopic stress.

Control of Gibbs free energy relationship between hen egg white lysozyme polymorphs under application of an external alternating current electric field

The Gibbs free energy relationship between bulk (tetragonal structure) and spherulitic crystals of hen egg white lysozyme was controlled under application of an external alternating current electric field. The distribution of phases differed depending on differences in the magnitude of the electrostatic energy contribution to the respective chemical potentials of the two solid phases.

High-throughput biological small-angle X-ray scattering with a robotically loaded capillary cell

A high-throughput biological small-angle X-ray scattering facility is described, which combines single-channel robotic pipetting with a capillary-based sample cell. The design parameters, sample rinsing protocol and effects of fluid dynamics on radiation damage are examined.

On the multiple orientation relationship of the Mg/γ-Mg₁₇Al₁₂ precipitation system

The origin of the multiple orientation relationship found in the Mg/γ-Mg₁₇Al₁₂ precipitation system has been rationally interpreted by a simplified invariant line analysis with consideration of the pseudo-twinning relationship between close-packed planes (), (11), (033), (411) and () in the precipitate phase γ-Mg₁₂Al₁₇.

Upgrade of automated sample exchanger SPACE

SPACE is an automated sample exchanger for cryo-cooled protein crystals, developed at SPring-8. This article reports the upgrading of SPACE.

Structural polytypism and residual strain in GaAs nanowires grown on Si(111) probed by single-nanowire X-ray diffraction

Using nanowire-resolved X-ray diffraction with a focused synchrotron beam, the structural composition, phase arrangement and residual strain of individual GaAs nanowires grown on Si(111) have been investigated.

Analysis of randomly oriented structures by grazing-incidence small-angle neutron scattering

A formalism is presented which allows the quantitative evaluation of grazing-incidence small-angle neutron scattering patterns from randomly oriented one-dimensional paracrystal domains with lamellar structure.

Dispersive spread of virtual sources by asymmetric X-ray monochromators

From the principles of X-ray dispersion in asymmetric Bragg reflections, typical dispersive multiple-crystal monochromators are analyzed to show that they may produce millimetre-sized virtual sources. Possible schemes to mitigate this problem for microfocusing are proposed.

In situ qu­antitative analysis of stress and texture development in forsterite aggregates deformed at 6 GPa and 1373 K

This paper presents a new protocol for the in situ investigation of differential stress, principal stress direction and lattice preferred orientation in low-symmetry materials deformed at high pressure and high temperature. The method has been successfully applied to data collected on the D-DIA deformation press at the X17B2 beamline of the National Synchrotron Light Source.

Modulation of quartz-like GeO₂ structure by Si substitution: an X-ray diffraction study of Ge_1−xSi_xO₂ (0 ≤ x < 0.2) flux-grown single crystals

Using X-ray diffraction, the high purity and high crystalline quality of millimetre-sized GeO₂-based crystals obtained using the flux method have been revealed. The effect of Ge replacement by Si on the distortion of the α-quartz-type GeO₂ structure was assessed by following the evolution of the intra-tetrahedral angle and other structural parameters.

Reckoning electromagnetic principles with polarimetric measurements of anisotropic optically active crystals

The problem of light propagation in optically active anisotropic crystals is studied with a unified theory of electromagnetic plane waves transmitted in a layered homogeneous bianisotropic system. The combined analytical and experimental methods described are applicable to the determination of the spectroscopic optical activity tensor of crystals.

Masquerade: removing non-sample scattering from integrated reflection intensities

A new technique is introduced to remove non-sample scattering from integrated reflection intensities by utilizing changes in relative scattering vectors. This approach is found to improve data quality.

Application of matrix decomposition algorithms for singular matrices to the Pawley method in Z-Rietveld

Improvements have been made to the nonlinear least-squares algorithms of the powder diffraction analysis program Z-Rietveld so that it can deal with singular matrices and intensity non-negativity constraints. Owing to these improvements, Z-Rietveld successfully executes the Pawley method without requiring any constraints on the integrated intensities, even in the case of severely or exactly overlapping peaks.

Application of constrained real-space refinement of flexible molecular fragments to automatic model building of RNA structures

New methods have been developed for locating phosphate groups and nucleic acid bases in the electron density of RNA structures. A program, RSR, has been created for the constrained refinement of molecular fragments in model-building methods based on a phased rotation–conformation–translation function, and the programs NUT, HEL and DHL have been upgraded and organized into a program system.

CrystalEye: automated aggregation, semantification and dissemination of the world's open crystallographic data

An automatic system for the aggregation, semantification and presentation of open crystallographic data is presented.

Nika: software for two-dimensional data reduction

Nika is a free open-source Igor Pro-based program for reduction of two-dimensional scattering data from area-detector small- and wide-angle scattering instruments to one-dimensional lineouts. It can be used in transmission and grazing-incidence geometries.

MossA: a program for analyzing energy-domain Mössbauer spectra from conventional and synchrotron sources

This paper introduces a new program for analyzing ⁵⁷Fe conventional and synchrotron energy-domain Mössbauer spectra.

Fragment Finder 2.0: a computing server to identify structurally similar fragments

The proposed web server is an updated version of a previously developed search engine and is useful for identifying structurally similar peptide fragments.

CrystFEL: a software suite for snapshot serial crystallography

A new suite of software is described, for processing data acquired from many small crystals illuminated `serially' by an X-ray free-electron laser.

New developments in the ATSAS program package for small-angle scattering data analysis

The paper presents new developments and amendments to the ATSAS package (version 2.4) for processing and analysis of isotropic small-angle scattering data.

Automated determination of the extinction symbol via electron diffraction data

A new statistical method for the automatic determination of the extinction symbol from electron diffraction data is described.

SIR2011: a new package for crystal structure determination and refinement

The main features of the program SIR2011 are described.

A fibre-based crystal mounting technique for protein cryocrystallography

A fibre-based crystal mounting technique for protein cryocrystallography has been developed.

Grazing-incidence in-plane X-ray diffraction on ultra-thin organic films using standard laboratory equipment

A setup for grazing-incidence in-plane X-ray diffraction using standard laboratory equipment and its application for organic thin-film and monolayer characterization is described.

Alexander McLeod Mathieson (1920–2011)

Hans Dachs (1927–2011)

Crystal Engineering. A Textbook

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