Laue classes
- Page ID
- 19056
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The Laue classes correspond to the eleven centrosymmetric crystallographic point groups. When absorption is negligible and Friedel's law applies, it is impossible to distinguish by diffraction between a centrosymmetric point group and one of its non-centrosymmetric subgroups.
Laue classes | Non-centrosymmetric groups having the same Laue class |
\({\bar 1}\) | 1 |
2/m | 2, m |
mmm | 222, 2mm |
\({\bar 3}\) | 3 |
\({\bar 3}m\) | 32, 3m |
4/m | 4, \({\bar 4}\) |
4/mmm | 422, \({\bar 4}2m\), 42m |
6/m | 6, \({\bar 6}\) |
6/mmm | 622, \({\bar 6}2m\), 62m |
\(m{\bar 3}\) | 23 |
\(m{\bar 3}m\) | 432, \({\bar 4}\)32 |