issue contents

Journal logoJOURNAL OF
ISSN: 1600-5767

December 1996 issue

Highlighted illustration

Cover illustration: Neutron scattering pattern in the (hk0) reciprocal-lattice plane from alpha-AgI at 520 K. The portion shown extends from 0 to 5.4 reciprocal-lattice units in both h and k. Courtesy of D. A. Keen, V. M. Nield and R. L. McGreevy.

research papers

J. Appl. Cryst. (1996). 29, 617-624
doi: 10.1107/S0021889896005122
link to html
The instrument function for energy-dispersive and angular- dispersive powder diffraction is presented.

J. Appl. Cryst. (1996). 29, 625-631
doi: 10.1107/S0021889896005134
link to html
The profile function of the Bragg reflection composed of the contributions of the apparent crystallite size and shape, of the anisotropic strain and of the instrument function is presented.

J. Appl. Cryst. (1996). 29, 632-637
doi: 10.1107/S0021889896006358
link to html
Thickness fluctuations in multilayers are shown to induce a strong diffuse term in grazing-incidence X-ray reflectivity (GIXR) patterns. Neglect of this effect causes alteration of average roughness and thickness values, derived by fitting of an ideal superlattice to the actual multilayer.

J. Appl. Cryst. (1996). 29, 638-645
doi: 10.1107/S002188989600636X
link to html
A commercial Agfa Arcus II scanner is found to be applicable for the photometry of gas electron-diffraction photographic plates.

J. Appl. Cryst. (1996). 29, 646-661
doi: 10.1107/S0021889896006589
link to html
The application of the indirect Fourier transformation and the square-root deconvolution procedure for a determination of the cross-section structure of cylindrical and polymer-like micelles is investigated using simulated small-angle scattering data.

J. Appl. Cryst. (1996). 29, 662-666
doi: 10.1107/S0021889896006693
link to html
The mean orientation of a cloud of individual orientations measured by EBSP (electron back-scattering patterns) is defined on the basis of quaternion algebra and illustrated on a phase- transformation problem in Ti alloys.

J. Appl. Cryst. (1996). 29, 667-673
doi: 10.1107/S0021889896007467
link to html
The two-stage method for crystal structure solution and analysis from powder data is analysed. The basic lines of a new approach are proposed.

J. Appl. Cryst. (1996). 29, 674-681
doi: 10.1107/S0021889896007431

J. Appl. Cryst. (1996). 29, 682-685
doi: 10.1107/S0021889896008382
link to html
A computer simulation of correlation effects in small-angle scattering is presented.

J. Appl. Cryst. (1996). 29, 686-691
doi: 10.1107/S0021889896006383
link to html
A new design is presented for a low-temperature sample environment compatible with the high resolution encountered at synchrotron beamlines. Its performance has been demonstrated in magnetic X-ray scattering experiments.

J. Appl. Cryst. (1996). 29, 692-699
doi: 10.1107/S0021889896007601
link to html
The performance of a high-resolution X-ray powder diffractometer working in the 3–470 K range is described. The high level of accuracy in peak position (to within 0.002°) and very good angular sensitivity (~10-4 °K−1) and an equal resolution in the whole range of temperature allow very accurate determination of the lattice parameters and crystal structure.

J. Appl. Cryst. (1996). 29, 700-706
doi: 10.1107/S002188989600814X
link to html
Ultrasonic measurements of the temperature-dependent elastic constants of potassium tetrachlorozincate are presented. An unusual temperature dependence of the C13 component reflects the onset of a soft mode prior to the onset of a ferroelectric-to- incommensurate phase transition.

J. Appl. Cryst. (1996). 29, 707-713
doi: 10.1107/S0021889896008199

J. Appl. Cryst. (1996). 29, 714-716
doi: 10.1107/S0021889896008631
link to html
Planarity of side chains in protein structures, compared with small-molecule database results.

J. Appl. Cryst. (1996). 29, 717-726
doi: 10.1107/S0021889896008655
link to html
Calculations show that, over a large range of cell size, Bragg resolution and X-ray beam width, a single 92 mm diameter micro- channel-plate (MCP) detector outperforms an array of four 256 × 256 mm multiwire proportional chambers. The advantages of the MCP detector are greatest at large cell size, high Bragg resolution and small beam width.

teaching and education

J. Appl. Cryst. (1996). 29, 727-735
doi: 10.1107/S002188989600619X
link to html
A course on diffraction is presented that uses computer simulations of structures and their Fourier transforms for effective teaching.

J. Appl. Cryst. (1996). 29, 736-737
doi: 10.1107/S0021889896006395
link to html
A generalized form of a symmetry operator has been derived by vector and matrix formalism. Typical applications of the formula are also provided.

cryocrystallography papers

J. Appl. Cryst. (1996). 29, 738-740
doi: 10.1107/S0021889896006188
link to html
A device allowing protein crystals to be prescreened in house for diffraction quality and merging statistics before data collection at a synchrotron-radiation facility is presented.

computer programs

J. Appl. Cryst. (1996). 29, 741-744
doi: 10.1107/S0021889896007194
link to html
The program RFLEXPL allows one to obtain cross-validated estimates for phase errors in structure factors calculated from an atomic model. It creates a file of structure factors in X-PLOR format that contains the information necessary to calculate weighted maps.

laboratory notes

J. Appl. Cryst. (1996). 29, 745
doi: 10.1107/S0021889896007418
link to html
A model of an air cooler in a crucible furnace for simultaneous regulation of different crystallization rates in a series of Tammann test tubes with the purpose of obtaining crystals is presented.


J. Appl. Cryst. (1996). 29, 746
doi: 10.1107/S0021889896099566

new commercial products

J. Appl. Cryst. (1996). 29, 746
doi: 10.1107/S0021889896099554

international union of crystallography

J. Appl. Cryst. (1996). 29, 746-748
doi: 10.1107/S0021889896099542

books received

J. Appl. Cryst. (1996). 29, 748
doi: 10.1107/S0021889896099530

J. Appl. Cryst. (1996). 29, 748
doi: 10.1107/S0021889896099529

J. Appl. Cryst. (1996). 29, 748
doi: 10.1107/S0021889896099517
Follow J. Appl. Cryst.
Sign up for e-alerts
Follow J. Appl. Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds