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Reindexing: Difference between revisions
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→Use of REIDX= for alternative indexing of given diffraction pattern
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Attention: whenever there is a possibility of alternative indexing, there is also a chance that the crystal (and its data) may be twinned! In the example above, the twinning law is h, -k , h-l . A good tool to identify this situation is [http://www.ccp4.ac.uk/html/sfcheck.html SFCHECK]. Whenever you see '''!!! WARNING !!! SOLUTION MAY NOT BE UNIQUE.''' in IDXREF.LP, you should be aware of this possible problem. | Attention: whenever there is a possibility of alternative indexing, there is also a chance that the crystal (and its data) may be twinned! In the example above, the (pseudo-merohedral) twinning law is h, -k , h-l . A good tool to identify this situation is [http://www.ccp4.ac.uk/html/sfcheck.html SFCHECK]. Whenever you see '''!!! WARNING !!! SOLUTION MAY NOT BE UNIQUE.''' in IDXREF.LP, you should be aware of this possible problem. | ||
FIXME: shortly discuss merohedral (Laue symmetry is of a lower order than the apparent crystal lattice symmetry) and non-merohedral twinning (example above) here. | FIXME: shortly discuss merohedral (Laue symmetry is of a lower order than the apparent crystal lattice symmetry) and non-merohedral twinning (example above) here. | ||