Cameras Weissenberg

Fig. 15. A Weissenberg photograph of (o-amino acid pyruvate aminotransferase (mercury derivative). A single bent triangular Si(lll) monochromator and a Weissenberg camera for macromolecular crystallography were used. The oscillation angle 30° the radius of the camera 287 mm, exposure time 4.7 min...

Sakabe, N. A focusing Weissenberg camera with multi-layer-line screens for macromolecular crystallography. J. Appl. Crysi. 16, 542-547 (1983). 

Figure 5.36 The synchrotron Weissenberg camera station for macromolecular crystallography (BL-6A2) at Photon Factory, Tsukuba. Figure kindly supplied by Professor N. Sakabe and reproduced with permission.

A very sensitive piezoelectric test (2) was negative and the space group PI assumed. Data were collected at room temperature with Zr filtered MoKa radiation on a Nonius integrating Weissenberg camera. The intensities of approximately 1100 reflections were estimated visually and reduced in the normal manner to structure amplitudes. The crystal was carefully gonio-metered and its dimensions measured and an accurate correction for absorption applied. 

Weissenberg Camera. A camera for X-ray diffraction analysis of crystal structures. The crystal is rotated, in the X-ray beam. The film is rotated and moved parallel to the axis of rotation. Weissenberg Rheogoniometer. In essence a cone and plate viscometer (q.v.), but with accessories and control systems to allow it to measure, as well as viscosity, elasticity and a wide range of flow properties such as dilatancy, thixotrophy, relaxation phenomena, etc in steady rotation or in torsional oscillation, over wide but controlled ranges of temperature and shear. 

Figure 18. Principle of the Weissenberg camera a) tqui-iiiclinalion axis b) Film c) Layer-line screen d) Crystal e) Equi-inclination angle setting...

Precession (Buerger) Camera. In contrast to the Weissenberg camera, the crystal carrier is now coupled to the film cassette so that both move in exactly the same way while the pattern is being recorded (Fig. 23). A direction in the crystal pre-cesses (precession angle /<) about the incident X-ray beam, so that reciprocal lattice points lying in a plane perpendicular to this crystal direction cut the reflection sphere. A precession pattern represents the reciprocal lattice in undistorted form... 

X-ray sources X-ray tubes Debye - Scherrer cameras two-circle powder diffractometers precession cameras Weissenberg cameras. 

Stoe Cie GmbH. P.O. Box 101302, Hilpert-strasse 10. 64295 Damistadt. Germany. Goniometer heads Debye-Scherrer cameras Guinier cameras Weissenberg cameras precession cameras Reciprocal Lattice Explorers powder diffrac-... 

Fig. 7.8. Equi-inclination Weissenberg camera, (a) is the arrangement for recording the zero layer and (b) is the arrangement for recording the first layer photographs. Note in (b), the crystal and the film cassette with the layer screen are rotated through an angle (5 and the layer line selector screen is shifted through a distance of C/2 = r tan <5 for recording the first layer diffraction cone. The incident X-ray beam coincides with the diffraction cone in this equi-inchnation setup...

Fig. 5.17. Vintage crystallographic apparatus a precession (left) and a Weissenberg camera.

Outline how you would interpret X-Ray diffraction data, if any, obtained for the following CPs and using the following X-Ray methods P(ANi)Cl P(Di-Ac)s Debye-Scherrer powder camera Weissenberg camera Precession camera Wide Angle X-Ray Diffraction Automated Diffractometer. 

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