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<p><font size="-1">Dear Malte <br>
</font></p>
<p><font size="-1">This is also a good place for asking, thanks for
that.<br>
</font></p>
<p><font size="-1"> It is always a good think to check and have a
clear idea of how things are working. <br>
</font></p>
<p><font size="-1">First thing to check the results in the two
cases; do they match ? <br>
</font></p>
<p><font size="-1">If this is the case, to understand what is
happening you could look at the symmetries that the program
finds in your system; they are always printed out in the xml
file. You should find operations for which t_rev has a true
value, meaning that that operation is usable only together with
the time reversal operation and others, for which has a false
value; these operations do not require the time reversal and
only these will be applied when you do not let the program to
use the the t_rev operation setting no_t_rev to true.</font></p>
<p><font size="-1">best regards <br>
</font></p>
<p><font size="-1">Pietro <br>
</font></p>
<p><font size="-1"> <br>
</font></p>
<p><font size="-1"> </font><br>
</p>
<div class="moz-cite-prefix">On 09/04/20 09:32, Malte Sachs wrote:<br>
</div>
<blockquote type="cite"
cite="mid:4c004549-6101-747f-0763-0f1d069f67cb@chemie.uni-marburg.de">
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<div class="moz-cite-prefix">
<div class="moz-cite-prefix">Dear Pietro,</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">thank you for your answer. I
thought if there is no time reversal symmetry also the
combinations with other symmetry operations should be
forbidden. Then it is quite similar to e.g. screw axes with a
combination of rotation+translation although there don't need
to be a rotation present?</div>
<div class="moz-cite-prefix">My system is orthorhombic. So the
twofold axis plus time reversal leave the spin direction
unchanged, right? Question marks started by comparing QE with
the LAPW-code Elk. In the Elk code it seems that
rotation+time-reversal is not used for k-point reduction.
However, this should then be a question for the Elk forum....</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">Best regards,<br>
Malte</div>
</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">Am 08.04.20 um 16:57 schrieb Pietro
Delugas:<br>
</div>
<blockquote type="cite"
cite="mid:13e493cd-113a-b556-996f-aa070631b566@sissa.it">
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<p><font size="-1">Dear Molte <br>
</font></p>
<p><font size="-1">your system could be symmetric under
operations made by a rotation + the time reversal
operation, in fact these are the operations that the
no_t_rev option disables, not the time reversal per se. <br>
</font></p>
<p><font size="-1">does the results with and without t_rev
compare correctly ? <br>
</font></p>
<p><font size="-1">best regards Pietro<br>
</font></p>
<div class="moz-cite-prefix">On 08/04/20 12:57, Malte Sachs
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:7c9b3409-4cd4-ffaf-6454-8a64077f3a82@chemie.uni-marburg.de">Dear
all, <br>
<br>
I am performing non-collinear magnetic calculations with
spin-orbit interactions with QE 6.5. As far as I have
understand, for a ferromagnetic system time-reversal symmetry
should be broken in this case. <br>
<br>
Although the program detects the right magnetic double point
group, the k-points grid is set up with time-reversal symmetry
and I have to set the no_t_rev flag manually to disable this.
Is there any reason why this isn't done by default (e.g. these
calculations can be done safely with a more reduced k-points
grid...)? Do I miss something? <br>
<br>
Best regards, <br>
<br>
Malte Sachs <br>
<br>
<br>
<br>
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Quantum ESPRESSO is supported by MaX (<a class="moz-txt-link-abbreviated" href="http://www.max-centre.eu/quantum-espresso" moz-do-not-send="true">www.max-centre.eu/quantum-espresso</a>)
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<pre class="moz-signature" cols="72">--
Malte Sachs
Anorganische Chemie, Fluorchemie
Philipps-Universität Marburg
Hans-Meerwein-Straße 4
35032 Marburg (Paketpost: 35043 Marburg)
Tel.: +49 (0)6421 28 - 25 68 0
<a class="moz-txt-link-freetext" href="http://www.uni-marburg.de/fb15/ag-kraus/" moz-do-not-send="true">http://www.uni-marburg.de/fb15/ag-kraus/</a></pre>
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<pre class="moz-quote-pre" wrap="">_______________________________________________
Quantum ESPRESSO is supported by MaX (<a class="moz-txt-link-abbreviated" href="http://www.max-centre.eu/quantum-espresso">www.max-centre.eu/quantum-espresso</a>)
users mailing list <a class="moz-txt-link-abbreviated" href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a>
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