Acta Crystallographica Section A

Foundations of Crystallography

Volume 69, Part 6 (November 2013)

research papers

Acta Cryst. (2013). A69, 603-610    [ doi:10.1107/S0108767313021740 ]

Distribution rules of systematic absences on the Conway topograph and their application to powder auto-indexing

R. Oishi-Tomiyasu

Abstract: This paper presents several general properties of systematic absences that are available before unit-cell parameters and the space group have been determined. The properties are given in the form of distribution rules of Miller indices corresponding to systematic absences on a topograph. A topograph is a graph whose edges are associated with a set of four lattice vectors satisfying Ito's equation 2(|l1*|2 + |l2*|2) = |l1* + l2*|2 + |l1* - l2*|2. It is possible to integrate global information about extinct reflections by using topographs. As an example of the application of these rules, a new powder auto-indexing algorithm is introduced, focusing on its theoretical aspects.

Keywords: systematic absences; powder auto-indexing; algorithm.

pdfdisplay filedownload file

Portable Document Format (PDF) file (116.4 kbytes)
[ doi:10.1107/S0108767313021740/sc5063sup1.pdf ]
Appendices A, B, C and D


To open or display or play some files, you may need to set your browser up to use the appropriate software. See the full list of file types for an explanation of the different file types and their related mime types and, where available links to sites from where the appropriate software may be obtained.

The download button will force most browsers to prompt for a file name to store the data on your hard disk.

Where possible, images are represented by thumbnails.

 bibliographic record in  format

  Find reference:   Volume   Page   
  Search:     From   to      Advanced search

Copyright © International Union of Crystallography
IUCr Webmaster