<html>
<head>
<meta content="text/html; charset=windows-1252"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<p>Dear Cyrille,</p>
<p><br>
</p>
<p>from the input description:<br>
<br>
'xy' : only v1_x and v2_y are moved<br>
<br>
'2Dxy' : only x and y components are allowed to change<br>
<br>
Thus, even in the case of cell_dofree='xy' I think the cell will
change. Anyway, the deviation from 120 DEG is quite small (119.43
DEG if I'm not wrong) - I don't know if this could be do to
numerical issues. Maybe try starting a new relaxation with a
hexagonal cell but smaller in-plane lattice vector of ~99.1%</p>
<p><br>
</p>
<p>Cheerio</p>
<p><br>
</p>
<p>Thomas<br>
</p>
<br>
<div class="moz-cite-prefix">On 07/25/17 09:08, BARRETEAU Cyrille
wrote:<br>
</div>
<blockquote
cite="mid:6E80B49CBC3D9F4694B510228B88EE3C2676E802@E-EXDAGE-A1.extra.cea.fr"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
<style type="text/css" id="owaParaStyle">P {margin-top:0;margin-bottom:0;}</style>
<div style="direction: ltr;font-family: Times New Roman;color:
#000000;font-size: 10pt;">
Dear QE community<br>
<br>
I have a question related to vc-relax and the option
cell_dofree.<br>
I want to relax a 2D metal-organic framework (MOF) with
hexagonal lattice (ibrav=4)<br>
Could you please explain what is the difference between
cell-dofree=xy and cell_dofree=2Dxy?<br>
<br>
I have noticed that when using cell_dofree=2Dxy the final
CELL_PARAMETER is no longer perfectly hexagonal (see below).
Should I use cell_dofree=xy instead and why?<br>
<br>
final:<br>
CELL_PARAMETERS (alat= 25.44640422)<br>
0.990921488 -0.000187347 0.000000000<br>
-0.495622997 0.858299558 0.000000000<br>
0.000000000 0.000000000 0.742630080<br>
<br>
Thanks in advance<br>
<br>
Cyrille<br>
<div><br>
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma; font-size:13px">
<div style="font-family:Tahoma;
font-size:13px">
<div style="font-family:Tahoma;
font-size:13px">
<div style="font-family:Tahoma;
font-size:13px">
<div style="font-family:Tahoma;
font-size:13px">
<div style="font-family:Tahoma;
font-size:13px">
<div style="font-family:Tahoma;
font-size:13px">
<div style="font-family:Tahoma;
font-size:13px">
<div style="font-family:Tahoma;
font-size:13px"><font size="2">========================<br>
</font>
<div
style="font-family:Tahoma;
font-size:13px">
<div
style="font-family:Tahoma;
font-size:13px">
<div
style="font-family:Tahoma;
font-size:13px">
<div
style="font-family:Tahoma;
font-size:13px">
<div
style="font-family:Tahoma;
font-size:13px">
<div
style="font-family:Tahoma;
font-size:13px"><b>Cyrille
Barreteau</b><br>
<div
style="font-family:Tahoma;
font-size:13px">
<div
style="font-family:Tahoma;
font-size:13px"><font size="2"><font face="Times New Roman">CEA Saclay<span
style="background-color:white"></span></font><font face="Times New
Roman">,
</font><font
face="Times
New Roman"><font
face="Times
New Roman"><font
face="Times
New Roman">IRAMIS,</font>
SPEC</font></font><font
face="Times
New Roman"><font
face="Times
New Roman"><span
style="background-color:white"> Bat. 771<br>
</span></font>91191
Gif sur Yvette
Cedex<span
style="background-color:white"></span>,
FRANCE
</font><br>
<font
face="Times
New Roman"><font
face="Times
New Roman">~~~~~~~~~~~~~~~~~~~~~~~~~~~~</font><br>
</font><font
face="Times
New Roman"><font
face="Times
New Roman"><font
face="Times
New Roman">+33
1 69 08 38 56
/</font></font></font><font
face="Times
New Roman"><font
face="Times
New Roman"><font
face="Times
New Roman"><font
face="Times
New Roman"><font
face="Times
New Roman">+33
6 47 53 66 52
(mobile) </font></font></font>
</font></font></font><br>
<font
face="Times
New Roman">email:
<a class="moz-txt-link-abbreviated" href="mailto:cyrille.barreteau@cea.fr">cyrille.barreteau@cea.fr</a> </font><font face="Times New Roman"><br>
Web: <a
moz-do-not-send="true"
href="http://iramis.cea.fr/Pisp/cyrille.barreteau/" tabindex="0">http://iramis.cea.fr/Pisp/cyrille.barreteau/</a></font><font
size="2"><br>
</font><font
size="2">========================</font></div>
</div>
</div>
</div>
<span
style="background-color:white;
font-family:Times
New Roman"><font
color="black"
size="2"><span
dir="ltr"
style="font-size:10pt"><font
size="2"><span
style="font-size:16px"></span></font></span></font></span></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<div style="font-family: Times New Roman; color: #000000;
font-size: 16px">
<hr tabindex="-1">
</div>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Pw_forum mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a>
<a class="moz-txt-link-freetext" href="http://pwscf.org/mailman/listinfo/pw_forum">http://pwscf.org/mailman/listinfo/pw_forum</a></pre>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Dr. rer. nat. Thomas Brumme
Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry
Leipzig University
Phillipp-Rosenthal-Strasse 31
04103 Leipzig
Tel: +49 (0)341 97 36456
email: <a class="moz-txt-link-abbreviated" href="mailto:thomas.brumme@uni-leipzig.de">thomas.brumme@uni-leipzig.de</a>
</pre>
</body>
</html>