Journal of Applied Crystallography

 

J. Appl. Cryst. (2006). 39, 473-482  [ doi:10.1107/S002188980601301X ]

A small-angle neutron scattering study of fine-scale NbC precipitation kinetics in the -Fe-Nb-C system

F. Perrard, A. Deschamps, F. Bley, P. Donnadieu and P. Maugis

Synopsis: Combined measurements using transmission electron microscopy, small-angle neutron scattering and chemical analysis, allow the absolute determination of NbC heterogeneous precipitation on dislocations in steels.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 483-486  [ doi:10.1107/S0021889806013008 ]

Phased rotation, conformation and translation function: theory and computer program

F. Pavelcik

Synopsis: The new phased rotation conformation and translation function (PRCTF) has been designed for automatic interpretation of electron density in X-ray crystallography, utilizing molecular fragments with conformational freedom. A computer program for the calculation of the PRCTF has been written.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 487-501  [ doi:10.1107/S0021889806015500 ]

Reciprocal-space mapping for simultaneous determination of texture and stress in thin films

D. Simek, R. Kuzel and D. Rafaja

Synopsis: A method of two-dimensional reciprocal-space mapping followed by Rietveld-type refinement of the maps has been developed and tested for stressed and strongly textured thin films with fibre texture.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 502-508  [ doi:10.1107/S0021889806016645 ]

Polycrystal elastic constants for triclinic crystal and physical symmetry

P. R. Morris

Synopsis: The problem of obtaining the Voigt average for the elastic stiffnesses with texture-describing weight functions has been solved for triclinic crystal and physical symmetries.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 509-518  [ doi:10.1107/S0021889806019546 ]

Anisotropic diffraction-line broadening due to microstrain distribution: parametrization opportunities

A. Leineweber

Synopsis: A new parametrization of microstrain broadening resulting from a correlated symmetry-invariant Gaussian microstrain distribution is presented. In contrast to earlier approaches, Cartesian coordinates are used, leading to expressions that allow easy identification of isotropic microstrain broadening.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 519-526  [ doi:10.1107/S0021889806016116 ]

XRPD/TEM studies of model high-temperature shift catalysts

R. E. Johnsen, A. M. Molenbroek and K. Ståhl

Synopsis: The combination of transmission electron microscopy (TEM) and in situ X-ray powder diffraction (XRPD) for the investigation of four model high-temperature shift catalysts makes it possible to obtain and compare information concerning the crystallite and particle shapes and sizes before, during and after the reduction of the synthesized hematite-based model catalyst to the active magnetite-based catalyst.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 527-535  [ doi:10.1107/S0021889806017894 ]

The revenge of the Patterson methods. I. Protein ab initio phasing

M. C. Burla, R. Caliandro, B. Carrozzini, G. L. Cascarano, L. De Caro, C. Giacovazzo, G. Polidori and D. Siliqi

Synopsis: An improved algorithm for Patterson deconvolution has been tested and compared with direct-methods approaches for ab initio crystal structure solution of macromolecules.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 536-543  [ doi:10.1107/S0021889806020395 ]

Rapid, accurate phase quantification of multiphase calcium phosphate materials using Rietveld refinement

J. W. Reid and J. A. Hendry

Synopsis: Two methods of Rietveld refinement have been employed to estimate the crystalline phase compositions of multiphase calcium phosphate mixtures containing calcium hydroxyapatite and alpha and beta tricalcium phosphate. The methods require approximately 10 min to complete, and are suitable for quality control of calcium phosphate production (and potentially other multiphase systems) when accuracy, precision and time are all significant considerations.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 544-549  [ doi:10.1107/S0021889806015925 ]

A novel method for crystal control: synthesis and design of strontium carbonate with different morphologies by supported liquid membrane

D.-M. Sun, Q.-S. Wu and Y.-P. Ding

Synopsis: A biomimetic supported liquid membrane (SLM) system was employed to control the morphology of strontium carbonate. Seeking the cooperative balance of the SLM, the modifier agent and its concentration is the key factor in this system.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 550-557  [ doi:10.1107/S0021889806016591 ]

Protein crystallography with a novel large-area pixel detector

G. Hülsen, C. Broennimann, E. F. Eikenberry and A. Wagner

Synopsis: The performance of a novel large-area hybrid pixel detector designed for macromolecular crystallography is reported. Crystallographic data were collected with synchrotron radiation in conventional mode and fine -sliced mode with continuous sample rotation.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 558-562  [ doi:10.1107/S0021889806017912 ]

Powder diffraction: the new automatic least-squares Fourier recycling procedure in EXPO2005

A. Altomare, C. Cuocci, C. Giacovazzo, A. G. G. Moliterni and R. Rizzi

Synopsis: A new weighting scheme has been implemented in the EXPO2005 least-squares Fourier recycling procedure for optimizing the structure model.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 563-570  [ doi:10.1107/S0021889806017857 ]

On the determination of step energies. Theoretical considerations and application to an anisotropic Kossel model

M. A. Deij, J. H. Los, H. Meekes and E. Vlieg

Synopsis: The inability to determine single-step energies in some cases is highlighted and a new method is introduced that uses the bonding topology and crystal structure geometry to calculate single-step energies

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 571-581  [ doi:10.1107/S0021889806018917 ]

Structural properties of ultra-low-energy ion-implanted silicon studied by combined X-ray scattering methods

L. Capello, T. H. Metzger, V. Holý, M. Servidori and A. Malachias

Synopsis: In this work a combination of X-ray scattering methods for the characterization of ultra-low-energy implanted Si wafers is presented. Grazing-incidence diffuse X-ray scattering is sensitive to the properties of the residual defects confined within thin crystalline layers; X-ray diffraction provides the depth distribution of the lattice strain and specular reflectivity provides the electron density profile.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 582-588  [ doi:10.1107/S002188980601939X ]

A discrete tomography algorithm for improving the quality of three-dimensional X-ray diffraction grain maps

A. Alpers, H. F. Poulsen, E. Knudsen and G. T. Herman

Synopsis: Statistics of the local morphology of grain boundaries is used to improve the quality of grain maps reconstructed from X-ray diffraction data.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 589-594  [ doi:10.1107/S0021889806019637 ]

In situ SAXS studies of the morphological changes of an alumina-zirconia-silicate ceramic during its formation

D. Le Messurier, R. Winter and C. M. Martin

Synopsis: Small-angle X-ray scattering is used at two energies, one either side of the zirconium K-edge, to probe the in situ formation of an alumina-zirconia-silicate ceramic.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 595-597  [ doi:10.1107/S0021889806019297 ]

Crystallography on mobile phones

I. Orlov, N. Schoeni and G. Chapuis

Synopsis: The first mobile phone application for crystallography training, Escher Mobile, is now available at http://escher.epfl.ch/mobile/.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 598-600  [ doi:10.1107/S0021889806017122 ]

Analytical formulation of the variance method of line-broadening analysis for Voigtian X-ray diffraction peaks

F. Sánchez-Bajo, A. L. Ortiz and F. L. Cumbrera

Synopsis: The variance method of line-broadening analysis of polycrystalline materials has been modified to include in its mathematical core the variance coefficients calculated analytically under the hypothesis of Voigtian line profiles.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 601-603  [ doi:10.1107/S0021889806021236 ]

Structural investigation of tetragonally stabilized ZrO₂ in -Al₂O₃-ZrO₂ composites

A. K. Deb, P. Chatterjee and S. P. Sen Gupta

Synopsis: The role of oxygen vacancies in tetragonal-phase stabilization of ZrO₂ has been studied by Rietveld refinement of X-ray powder diffraction data.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 604-606  [ doi:10.1107/S0021889806022953 ]

Picolitre-scale crystallization of membrane proteins

V. Cherezov and M. Caffrey

Synopsis: Crystallization of membrane proteins for three-dimensional structure determination can now be performed at the unprecedented picolitre-scale enabling the performance of thousands of crystallogenesis trials with just micrograms of protein.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 607-614  [ doi:10.1107/S0021889806014075 ]

ISODISPLACE: a web-based tool for exploring structural distortions

B. J. Campbell, H. T. Stokes, D. E. Tanner and D. M. Hatch

Synopsis: ISODISPLACE is an internet-based tool for exploring displacive structural phase transitions. It allows a user interactively to visualize and manipulate distortion modes induced by irreducible representations of the parent space-group symmetry.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 615-617  [ doi:10.1107/S0021889806014154 ]

GENEFP: a full-profile fitting program for X-ray powder patterns using the genetic algorithm

Z. J. Feng and C. Dong

Synopsis: The genetic algorithm is used in a full-profile fitting program to search for proper fundamental parameters that have large uncertainties.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 618-619  [ doi:10.1107/S0021889806014518 ]

SITCOM: a program for comparing sites in macromolecular substructures

F. Dall'Antonia and T. R. Schneider

Synopsis: The program SITCOM, which can be used for the comparison of macromolecular substructures from different sources for validation purposes, and for the construction of a consensus model containing sites from different substructures, is described.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 620  [ doi:10.1107/S0021889806021996 ]

VRML general position diagrams of magnetic space groups

J. S. Burke, N. R. Cordisco and D. B. Litvin

Synopsis: Three-dimensional general position diagrams of the superfamilies of all non-cubic magnetic space groups have been developed. The diagrams can be rotated and zoomed to aid in the visualization of the general position diagrams and include both the general positions of the atoms and the general orientations of the associated magnetic moments.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 621-625  [ doi:10.1107/S0021889806015627 ]

A validating CIF parser: PyCIFRW

J. R. Hester

Synopsis: The PyCIFRW Python package provides a conceptually simple interface to CIF files for Python programmers, with optional validation against DDL dictionaries.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 626-629  [ doi:10.1107/S0021889806021856 ]

A simple and low-cost solution for the automation of X-ray powder diffractometers with chart recorder output

M. Jayaprakasan, V. Kannan and P. Ramasamy

Synopsis: A simple low-cost solution for automation of conventional X-ray powder diffractometers, using a PC to collect, store and analyze the data quickly, is described.

Online 15 July 2006

 

J. Appl. Cryst. (2006). 39, 630  [ doi:10.1107/S0021889806025969 ]

Stephen Fleet

Online 15 July 2006