<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
</head>
<body>
<style type="text/css" style="display:none;"><!-- P {margin-top:0;margin-bottom:0;} --></style>
<div id="divtagdefaultwrapper" style="font-size:12pt;color:#000000;font-family:Calibri,Arial,Helvetica,sans-serif;">
<p>Dear Tomas</p>
<p>Are you a hokey player? I suppose not!<br>
</p>
<p>The problem with this is that the cell goes from CXY to P then in the cell the number of atoms doubles.</p>
<p>What I did is to see the positions of the changes of the atoms with sgroup</p>
<p>Before sgroup:</p>
<p><span></span><span></span></p>
<div> 1: X=0.50000000 Y=0.00000000 Z=0.63000000<br>
2: X=0.00000000 Y=0.00000000 Z=0.63000000<br>
3: X=0.50000000 Y=0.25000000 Z=0.38122315<br>
3: X=0.50000000 Y=0.75000000 Z=0.38122315<br>
4: X=0.50000000 Y=0.25000000 Z=0.87877685<br>
4: X=0.50000000 Y=0.75000000 Z=0.87877685<br>
5: X=0.75000000 Y=0.00000000 Z=0.35739347<br>
5: X=0.25000000 Y=0.00000000 Z=0.35739347<br>
</div>
................
<p></p>
<p></p>
<div>16: X=0.50000000 Y=0.75000000 Z=0.73290499<br>
17: X=0.25000000 Y=0.34304549 Z=0.35413297<br>
17: X=0.75000000 Y=0.65695451 Z=0.35413297<br>
17: X=0.75000000 Y=0.34304549 Z=0.35413297<br>
17: X=0.25000000 Y=0.65695451 Z=0.35413297<br>
18: X=0.75000000 Y=0.15695450 Z=0.90586703<br>
</div>
=============
<p></p>
<p>After sgroup</p>
<p></p>
<div> 1: X=0.63000000 Y=0.63000000 Z=0.50000000<br>
2: X=0.63000000 Y=0.63000000 Z=0.00000000<br>
3: X=0.63122315 Y=0.38122315 Z=0.00000000<br>
4: X=0.63122315 Y=0.38122315 Z=0.50000000<br>
5: X=0.12877685 Y=0.87877685 Z=0.00000000<br>
6: X=0.12877685 Y=0.87877685 Z=0.50000000<br>
7: X=0.35739347 Y=0.35739347 Z=0.25000000<br>
7:X= 0.35739347 Y=0.35739347 Z=0.75000000<br>
</div>
.............................
<p></p>
<p></p>
<div>20: X=0.98290499 Y=0.73290499 Z=0.50000000<br>
21: X=0.51108748 Y=0.35413297 Z=0.25000000<br>
21:X= 0.51108748 Y=0.35413297 Z=0.75000000<br>
22: X=0.69717846 Y=0.35413297 Z=0.25000000<br>
22:X= 0.69717846 Y=0.35413297 Z=0.75000000<br>
23: X=0.74891253 Y=0.90586703 Z=0.25000000<br>
</div>
================
<p></p>
<p>As you can see</p>
<p>a=>c</p>
<p>b+c=>a</p>
<p>c=>b</p>
<p>then you can see how the atoms split, for example <br>
</p>
<p><span>atoms '3' split into '3' and '4'</span><br>
</p>
<p>atoms '17' split into '21' and '22'</p>
<p>one have to take into account that the original structure is <br>
</p>
<p>CXY and a,b are equivalent to a+.5,b+.5</p>
<p><br>
</p>
<p>The <span>b+c=>a</span> is the consequence of the 90 => 135 degrees</p>
<p><br>
</p>
<p>I would be easy to make a program to change 135 => 90</p>
<p><br>
</p>
<p>Thank for your comments</p>
<p><br>
</p>
<p> Pablo<br>
</p>
</div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>De:</b> Wien <wien-bounces@zeus.theochem.tuwien.ac.at> en nombre de Tomas Kana <kana@seznam.cz><br>
<b>Enviado:</b> viernes, 14 de octubre de 2016 05:24:55 a. m.<br>
<b>Para:</b> A Mailing list for WIEN2k users<br>
<b>Asunto:</b> Re: [Wien] Change of structure symmetry</font>
<div> </div>
</div>
<div>Dear Pablo, <br>
I tried to play with your structure and I succeeded. <br>
First, run <br>
x supercell <br>
always one cell in x- y- and z- directions <br>
zero shift in all directions <br>
Enter your target lattice type:<br>
P <br>
(you must choose primitive lattice in order to break <br>
the symmetries you do not want there). <br>
Zero vacuum in all directions. <br>
Then <br>
cp TiO2-sup_super.struct TiO2-sup.struct <br>
Edit the TiO2-sup.struct file and find the two Cu atoms. <br>
Rewrite the space after first Cu to 1. <br>
Rewrite the space after second Cu to 2. <br>
Or do these two things comfortably using w2web. <br>
You must have them inequivalent. <br>
By the way, are you sure that the vacuum you have for your slab is <br>
sufficient? When I use slabs I try to have vacuum around 20 bohrs. <br>
Then run <br>
x sgroup <br>
By checking TiO2-sup.outputsgroup you see that sgroup has chosen <br>
monoclinic lattice but with all three angles equal to 90 degrees. <br>
(Space group 56 6 Pm) <br>
Then, I STRONGLY RECOMMEND TO ERASE ONE OF THE Cu ATOMS, <br>
probably the one at the position 0 0 0. <br>
It worked on my computer. <br>
HTH <br>
Tomas <br>
</div>
</body>
</html>