ISSN:
1600-5724
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
Transmission Kikuchi line patterns from wedge-shaped crystals of natural spinel have been studied. Especially near line intersections, extensive contrast anomalies attributable to multiple-beam interactions were observed, such as enhanced and diminished line segments, split lines and line segments which can not be indexed as ordinary Kikuchi lines. Several effects sometimes combine to form extensive patterns related to the Kikuchi envelope. The observed patterns are compared with calculated line contrast using several interacting beams. Most of the effects can be explained through three interacting beams; hence, three-beam effects in Kikuchi patterns are discussed in some detail. General rules for the dependence of contrast anomalies on signs and sizes of the Fourier potentials are derived. It is pointed out that, because of the wide range of diffraction conditions recorded in one exposure and the elimination of thickness-dependent oscillations, Kikuchi patterns give a very useful picture of the angular extent of the most important dynamic interactions. Applications of the results in connection with other diffraction techniques are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0567739469001343
