View source for Zonal reflection conditions

<font color="blue">Conditions de réflexion zonales</font> (''Fr''). <font color="red">Zonale Auslöschungen</font> (''Ge''). <font color="black">Condizioni di riflessione zonali</font> (''It'').


== Definition ==

The zonal reflection conditions are the general [[reflection conditions]] due to the presence of glide planes. The resulting conditions apply only to two-dimensional sets of reflections, ''i.e.'' to reciprocal-lattice nets containing the origin (such as ''hk''0, ''h''0''l'', 0''kl'', ''hhl''). For instance, for a glide plane parallel to (001):

<table border cellspacing=0 cellpadding=5 align=center>
<tr> 
<th> Type of reflection</th><th>Reflection condition</th> <th> Glide vector</th><th> Glide plane</th> </tr>
<tr> <td rowspan=4>0''kl''</td> <td>''k'' = 2 ''n''</td> <td>'''b'''/2</td><td> ''b''</td></tr>
<tr> 
<td>''l'' = 2 ''n''</td><td>'''c'''/2</td> <td> ''c''</td></tr>
<tr> 
<td>''k'' + ''l'' = 2 ''n''</td><td>'''b'''/2 + '''c'''/2</td> <td> ''n''</td></tr>
<tr> 
<td>''k'' + ''l'' = 4 ''n''<br>''k'', ''l'' = 2''n''</td><td>'''b'''/4 &plusmn; '''c'''/4</td> <td> ''d''</td></tr>
</table>

The zonal reflection conditions are listed in Table 2.1.3.7 of ''International Tables for Crystallography, Volume A'', 6th edition. 

==See also ==
*[[Reflection conditions]]
*Chapter 2.1.3.13 of ''International Tables for Crystallography, Volume A'', 6th edition

[[Category:X-rays]]