Difference between revisions of "Integral reflection conditions"
From Online Dictionary of Crystallography
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<td> ''h'' − ''k'' = 3''n''</td> <td>hexagonally centred</td> <td> ''H''</td></tr> | <td> ''h'' − ''k'' = 3''n''</td> <td>hexagonally centred</td> <td> ''H''</td></tr> | ||
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+ | <td> ''h'' + ''k'' + ''l'' = 3''n''</td> <td>D centred</td> <td> ''D''</td></tr> | ||
</table> | </table> | ||
Latest revision as of 12:59, 27 August 2018
Conditions de réflexion intégrales (Fr). Integrale Auslöschungen (Ge). Ausencias integrales (Sp).
Definition
The integral reflections are the general reflection conditions appearing when a multiple (non-primitive) cell is used to describe the Bravais lattice of a crystal. They are given in the table below:
Reflection condition |
Centring type of cell | Centring symbol |
---|---|---|
None | Primitive | P R (rhombohedral axes) |
h + k = 2n | C-face centred | C |
k + l = 2n | A-face centred | A |
l + h = 2n | B-face centred | B |
h + k + l = 2n | body centred | I |
h + k, h + l and k + l = 2n or: | all-face centred | F |
− h + k + l = 3n | rhombohedrally centred, obverse |
R (hexagonal axes) |
h − k + l = 3n | rhombohedrally centred, reverse | |
h − k = 3n | hexagonally centred | H |
h + k + l = 3n | D centred | D |
See also
- Chapter 2.1.3.13 of International Tables for Crystallography, Volume A, 6th edition