Twinning: Difference between revisions

26 bytes removed ,  31 August 2021
→‎Tests for Twinning: remove empty section
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For non-merohedral twins, the twin law does not belong to the crystal class of the structure nor to the metric symmetry of the cell. Therefore the different reciprocal lattices do not overlap exactly. There are three types of reflections, non-overlapped, partially overlapped and exactly overlapped reflections. Here the problems start in the data collection. If both twin domains are similar in size, there are often problems with the cell determination and usual automatic indexing programs fail.  More than one orientation matrix is needed to index all reflections. In the integration process the information of all matrices should be used.
For non-merohedral twins, the twin law does not belong to the crystal class of the structure nor to the metric symmetry of the cell. Therefore the different reciprocal lattices do not overlap exactly. There are three types of reflections, non-overlapped, partially overlapped and exactly overlapped reflections. Here the problems start in the data collection. If both twin domains are similar in size, there are often problems with the cell determination and usual automatic indexing programs fail.  More than one orientation matrix is needed to index all reflections. In the integration process the information of all matrices should be used.


== Tests for Twinning ==


== Solution ==
== Solution ==
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