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<div class="moz-cite-prefix">FYI, the subprogram that does that is
spacegroup (refer to section "9.14 spacegroup" in the WIEN2k 14.2
usersguide on page 195 [
<a class="moz-txt-link-freetext" href="http://www.wien2k.at/reg_user/textbooks/usersguide.pdf">http://www.wien2k.at/reg_user/textbooks/usersguide.pdf</a> ]).<br>
<br>
For example, Ti has the nonequivalent position (0,0,0), and it
should have a Ti equivalent position of (0.5,0.5,0.5), as taken
from TiO2.struct [
<a class="moz-txt-link-freetext" href="https://github.com/hpcugent/easybuild-easyconfigs/blob/master/easybuild/easyconfigs/w/WIEN2k/TiO2.struct">https://github.com/hpcugent/easybuild-easyconfigs/blob/master/easybuild/easyconfigs/w/WIEN2k/TiO2.struct</a>
]:<br>
<br>
TiO2
<br>
P LATTICE,NONEQUIV.ATOMS:
2136_P42/mnm <br>
MODE OF CALC=RELA
unit=bohr <br>
8.682000 8.682000 5.592000 90.000000 90.000000
90.000000 <br>
ATOM -1: X=0.00000000 Y=0.00000000 Z=0.00000000 <=
Nonequivalent Ti position<br>
MULT= 2 ISPLIT= 8 <br>
-1: X=0.50000000 Y=0.50000000 Z=0.50000000 <= Equivalent
Ti position<br>
Ti NPT= 781 R0=0.00005000 RMT= 2.0000 Z: 22.0 <br>
...<br>
<br>
Run the WIEN2k spacegroup program in a terminal:<br>
<br>
username@computername:~/wiendata/TiO2$ spacegroup<br>
Type in cell parameters : 8.682000 8.682000 5.592000 90.000000
90.000000 90.000000<br>
Type in space group symbol : P42/mnm<br>
Name of the 1st atom : Ti<br>
Coordinates of the 1st atom : 0.00000000 0.00000000 0.00000000<br>
Ti/1 0.00000000 0.00000000 0.00000000<br>
Ti/2 0.50000000 0.50000000 0.50000000 <= Here, it
found the equivalent Ti position to be (0.5,0.5,0.5) as expected
(for the 2a site [
<a class="moz-txt-link-freetext" href="http://www.cryst.ehu.es/cgi-bin/cryst/programs//nph-wp-list?gnum=136&what=wpos">http://www.cryst.ehu.es/cgi-bin/cryst/programs//nph-wp-list?gnum=136&what=wpos</a>
]).<br>
Name of the 2nd atom : <br>
username@computername:~/wiendata/TiO2$<br>
<br>
If you prefer a Windows graphic user interface, there is the EQUIV
program [ <a class="moz-txt-link-freetext" href="http://www.ccp14.ac.uk/tutorial/lmgp/equiv.htm">http://www.ccp14.ac.uk/tutorial/lmgp/equiv.htm</a> ]. I
believe EQUIV might be based on the getspec code [
<a class="moz-txt-link-freetext" href="http://www.iucr.org/resources/other-directories/software/getspec">http://www.iucr.org/resources/other-directories/software/getspec</a>
].<br>
<br>
I'm not aware of any article describing the insides of the
spacegroup program or how it was written. It is likely, though,
that the "International Tables for Crystallography" [
<a class="moz-txt-link-freetext" href="http://dx.doi.org/10.1107/97809553602060000001">http://dx.doi.org/10.1107/97809553602060000001</a> ] were used as a
reference.<br>
<br>
Try searching journals out there related to computational
crystallography. For example, the Journal of Applied
Crystallography might be a good one to search [
<a class="moz-txt-link-freetext" href="http://dx.doi.org/10.1107/S0021889875011004">http://dx.doi.org/10.1107/S0021889875011004</a> ,
<a class="moz-txt-link-freetext" href="http://dx.doi.org/10.1107/S0021889804031528">http://dx.doi.org/10.1107/S0021889804031528</a> ].<br>
<br>
On 2/15/2016 7:28 AM, Tomas Kana wrote:<br>
</div>
<blockquote cite="mid:AmD.LHYK.6qG4k0O4GK9.1MmU2M@seznam.cz"
type="cite">
<p>Dear Amir, </p>
<p>At first, you should specify the structure using the Space
group number <br>
</p>
<p>(for example in w2web or makestruct_lapw). Then, you specify
only </p>
<p>one position and the remaining positions (belonging to the
space group) </p>
<p>are generated automatically. </p>
<p>Hope this helps </p>
<p>Tomas </p>
<br>
<blockquote>
<div>
<div style="color:#000; background-color:#fff;
font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial,
Lucida Grande, Sans-Serif;font-size:16px">
<div>Dear WIEN2k users,</div>
<div>Please let me know</div>
<div>How can i generate equivalent positions for a atom or
different atoms for a compound with a specific symmetry?</div>
<div>I would like to know background of it for writing a
program.</div>
<div>Sincerely,</div>
<div>Amir</div>
</div>
</div>
</blockquote>
</blockquote>
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