Zonal reflection conditions

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== Definition ==
== Definition ==
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The zonal reflection conditions are the general [[reflection conditions]] due to the presence of glide planes.
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The zonal reflection conditions are the general [[reflection conditions]] due to the presence of glide planes. The resulting conditions apply only to twodimensional 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):
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<table border cellspacing=0 cellpadding=5 align=center>
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<tr>
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<th> type of reflection</th><th>reflection condition</th> <th> glide vector</th><th> glide plane</th> </tr>
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<tr> <td rowspan=4>0''kl''</td> <td>''k'' = 2 ''n''</td> <td>'''b'''/2</td><td> ''b''</td></tr>
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<tr>
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<td>''l'' = 2 ''n''</td><td>'''c'''/2</td> <td> ''c''</td></tr>
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<tr>
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<td>''k'' + ''l'' = 2 ''n''</td><td>'''b'''/2 + '''c'''/2</td> <td> ''n''</td></tr>
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<tr>
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<td>''k'' + ''l'' = 4 ''n''<br>''k'', ''l'' = 2''n''</td><td>'''b'''/4 &plusmn; '''c'''/4</td> <td> ''d''</td></tr>
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</table>
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The zonal reflection conditions are listed in Table 2.2.13.2 of ''International Tables of Crystallography, Volume A''.  
==See also ==
==See also ==

Revision as of 07:26, 5 May 2006

Conditions de réflexion zonales (Fr).

Definition

The zonal reflection conditions are the general reflection conditions due to the presence of glide planes. The resulting conditions apply only to twodimensional sets of reflections, i.e. to reciprocal-lattice nets containing the origin (such as hk0, h0l, 0kl, hhl). For instance, for a glide plane parallel to (001):

type of reflectionreflection condition glide vector glide plane
0kl k = 2 n b/2 b
l = 2 nc/2 c
k + l = 2 nb/2 + c/2 n
k + l = 4 n
k, l = 2n
b/4 ± c/4 d

The zonal reflection conditions are listed in Table 2.2.13.2 of International Tables of Crystallography, Volume A.

See also

reflection conditions
Section 2.2.13 of International Tables of Crystallography, Volume A