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International
Tables for Crystallography Volume C Mathematical, physical and chemical tables Edited by E. Prince © International Union of Crystallography 2006 |
International Tables for Crystallography (2006). Vol. C. ch. 2.2, p. 34
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The conventional Weissenberg method uses a moving film in conjunction with the rotation of the crystal and a layer-line screen. This allows:
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The Weissenberg method is not widely used now. In small-molecule crystallography, quantitative data collection is usually performed by means of a diffractometer.
Weissenberg geometry has been revived as a method for macromolecular data collection (Sakabe, 1983![[link]](/graphics/greenarr.gif)
, 1991), exploiting monochromatized synchrotron radiation and the image plate as detector. Here the method is used without a layer-line screen where the total rotation angle is limited to ![[\sim15^\circ]](/teximages/cbch2o2/cbch2o2fi84.svg)
; this is a significant increase over the rotation method with a stationary film. The use of this effectively avoids the presence of partial reflections and reduces the total number of exposures required. Provided the Weissenberg camera has a large radius, the X-ray background accumulated over a single spot is actually not serious. This is because the X-ray background decreases approximately according to the inverse square of the distance from the crystal to the detector.
The following Subsections 2.2.4.2 and 2.2.4.3 describe the standard situation where a layer-line screen is used.
References
Sakabe, N. (1983). A focusing Weissenberg camera with multilayer-line screens for macromolecular crystallography. J. Appl. Cryst. 16, 542–547.Google Scholar
Sakabe, N. (1991). X-ray diffraction data collection systems for modern protein crystallography with a Weissenberg camera and an imaging plate using synchrotron radiation. Nucl. Instrum. Methods, A303, 448–463.Google Scholar
