You are here: Home :: Area NEM :: Chemistry :: Inorganic chemistry

Radomir Kuzel

Kinematical diffraction by distorted crystals – dislocation X-ray line broadening

Keywords: Dislocation density, Diffraction line broadening, Real structure, Structural inhomogeneities, X-ray diffraction

The current state of the description and evaluation of dislocation-induced X-ray diffraction line broadening has been reviewed. The diffraction-line broadening can be analyzed in terms of line width, moments or Fourier coefficients. However, in the last years, whole pattern fitting has become the most popular method of evaluation. The line width is proportional to the Burgers vector of dislocations, to the square-root of dislocation density and to the so-called orientation (contrast) factor. The orientation factor determines the hkl dependence of broadening and is a function of the elastic characteristics of the material investigated and the orientation of the diffraction vector with respect to the Burgers vector and dislocation line. Since a completely random dislocation distribution of dislocations is impossible, another parameter connected to the dislocation correlation (cut-off radius) must be included in the description. The theory of dislocation-induced line broadening has been developed many years ago, but it is still not completely satisfactory from the point of view of its practical application to line profile analysis. General problems of present line profile analysis on samples with dislocations are mentioned. This includes consideration 2^nd kind stresses, texture and sample inhomogeneities.

Zeitschrift für Kristallographie, Oldenbourg Wissenschaftsverlag

Print ISSN: 0044-2968
Volume: 222, 03/2007
Pages: 136 - 149

Show full article (external site)

Show all available items of this journal

 

Area NEM