Difference between revisions of "Integral reflection conditions"
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+ | == Definition == | ||
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+ | The integral reflections are the general [[reflection conditions]] due to the centring of cells. They are given in the table below: | ||
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<table border cellspacing=0 cellpadding=5 align=center> | <table border cellspacing=0 cellpadding=5 align=center> | ||
<caption align=top> '''Integral reflection conditions for centred lattices.''' </caption> | <caption align=top> '''Integral reflection conditions for centred lattices.''' </caption> |
Revision as of 07:13, 5 May 2006
Definition
The integral reflections are the general reflection conditions due to the centring of cells. They are given in the table below:
<tr align=left> <td>k + l = 2n</td> <td>A-face centred</td> <td>A</th> </tr> <tr align=left> <td>l + h = 2n</td> <td>B-face centred</td> <td>B</td> </tr> <tr align=left> <td>h + k + l = 2n</td> <td>body centred</td> <td>I</th> </tr> <tr align=left> <td>h + k, h + l andk + l = 2n or:
h, k, l all odd or all
even (‘unmixed’)</td> <td>all-face centred</td> <td> F</th> </tr> <tr align=left> <td> − h + k + l = 3n</td> <td> rhombohedrally
centred, reverse
setting </td><td rowspan=2>R (hexagonal axes)</td>></tr> <tr align=left> <td> h − k + l = 3n</td> <td> rhombohedrally
centred, obverse
setting (standard)</td> </tr> <tr align=left> <td> h − k = 3n</td> <td>hexagonnally centred</td> <td> H</td> </table>
Reflection condition |
Centring type of cell | Centring symbol |
---|---|---|
None | Primitive | P R (rhombohedral axes) |
h + k = 2n | C-face centred | C</th> |