Rotation/oscillation geometry
Helliwell, J. R.,
International Tables for Crystallography
(2006).
Vol. C,
Section 2.2.3,
p.
[ doi:10.1107/97809553602060000577 ]
of reciprocal space can be recorded within a smaller angle. There is a blind region close to the rotation axis; this is detailed in Subsection
2.2.3.5 .
2.2.3.2. Diffraction coordinates
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Figs.
2.2.3.1(a) to (d ...
Blind region
Helliwell, J. R.,
International Tables for Crystallography
(2006).
Vol. C,
Section 2.2.3.5,
p.
[ doi:10.1107/97809553602060000577 ]
ray techniques
In normal-beam geometry, any relp lying close to the rotation axis will not be stimulated at all. This situation is shown in Fig.
2.2.3.4
. The blind region has a radius of and is therefore strongly ...
Relationship of reciprocal-lattice coordinates to crystal system parameters
Helliwell, J. R.,
International Tables for Crystallography
(2006).
Vol. C,
Section 2.2.3.3,
p.
[ doi:10.1107/97809553602060000577 ]
ray techniques
The reciprocal-lattice coordinates, etc . used earlier, refer to an axial system fixed to the crystal, of Fig.
2.2.3.3
. Clearly, a given relp needs to be brought into the Ewald sphere by the rotation ...
Diffraction coordinates
Helliwell, J. R.,
International Tables for Crystallography
(2006).
Vol. C,
Section 2.2.3.2,
p.
[ doi:10.1107/97809553602060000577 ]
ray techniques
Figs.
2.2.3.1(a) to (d) are taken from IT II (1959, p. 176). They neatly summarize the geometrical principles of reflection, of a monochromatic beam, in the reciprocal lattice for the general case ...
General
Helliwell, J. R.,
International Tables for Crystallography
(2006).
Vol. C,
Section 2.2.3.1,
p.
[ doi:10.1107/97809553602060000577 ]
the diffraction spots, is 180° + . If the crystal has additional symmetry, then a complete asymmetric unit of reciprocal space can be recorded within a smaller angle. There is a blind region close to the rotation axis; this is detailed in Subsection
2.2.3.5 ...
Maximum oscillation angle without spot overlap
Helliwell, J. R.,
International Tables for Crystallography
(2006).
Vol. C,
Section 2.2.3.4,
p.
[ doi:10.1107/97809553602060000577 ]
as to reduce the background noise in the diffraction images and also to avoid loss of any data because of spot overlap.
References
Weisgerber, S. &
Helliwell,
J.
R. (1993). High-resolution crystallographic studies of native ...
