[QE-developers] Finding all symmetry operations correctly

[박민규]

Let me explain again.

Given magnetic space group of MnF2 in its antiferromagnetic phase is P4_2’/mnm’ (136.499),
there should be 16 symmetry operations if QE can detect all symmetry operations.
While if you see pwscf.out.afm I attach, there are only 8 symmetry operations.
(I’m only counting the number of operations, but each operations should be identified correctly after all.)
This is the problem I have.

I think this is a limitation that has been noticed and discussed recently. It shouldn't be too difficult to fix actually

If this is the case, sorry for repeating this.

Best,
============================================
Minkyu Park
Research Institute of Basic Sciences, University of Ulsan,
93, Daehak-ro, Nam-gu, Ulsan, 44610 Republic of Korea
minkyupark at ulsan.ac.kr<mailto:minkyupark at ulsan.ac.kr>
+82-52-259-1473
============================================

On 23 May 2020, at 1:22 AM, 박민규 <minkyupark at ulsan.ac.kr<mailto:minkyupark at ulsan.ac.kr>> wrote:


well yes this is the way you specify that the two atoms should be treated as different... (for instance because of different starting magnetizations in and anti-ferromagnetic  configuration)

My original point was this.
For an antiferromagnetic configuration with non-symmorphic space group,
QE does not recognize part of symmetry operations.

============================================
Minkyu Park
Research Institute of Basic Sciences, University of Ulsan,
93, Daehak-ro, Nam-gu, Ulsan, 44610 Republic of Korea
minkyupark at ulsan.ac.kr<mailto:minkyupark at ulsan.ac.kr>
+82-52-259-1473
============================================

On 23 May 2020, at 1:12 AM, Stefano de Gironcoli <degironc at sissa.it<mailto:degironc at sissa.it>> wrote:


well yes this is the way you specify that the two atoms should be treated as different... (for instance because of different starting magnetizations in and anti-ferromagnetic  configuration)

why would anyone define two atoms of the same species as different types otherwise ?

stefano

On 22/05/20 18:02, 박민규 wrote:
Dear all,

Sorry for the insufficient information.

I performed two calculations one is with one type of Mn and the other is with two type of Mn.
Both of them are done without magnetic moments with relativistic pseudopotentials.
With one type of Mn, I get 16 operations. While with two types of Mn, I get 8 operations.
I attach input and output files.

Best,
============================================
Minkyu Park
Research Institute of Basic Sciences, University of Ulsan,
93, Daehak-ro, Nam-gu, Ulsan, 44610 Republic of Korea
minkyupark at ulsan.ac.kr<mailto:minkyupark at ulsan.ac.kr>
+82-52-259-1473
============================================

On 23 May 2020, at 12:47 AM, Lorenzo Paulatto <paulatz at gmail.com<mailto:paulatz at gmail.com>> wrote:

I think the problem occurs because QE treats each type of atom (ntyp) differently even though they are actually same species.


Hello Minkyu, QE always consider all atoms of the same species equivalent, unless you tell it explicitly not to. I think you should provide a reproducible example if you think there is a real bug. You can do it here, or on the gitlab bug tracker.

regards



--
Lorenzo Paulatto - Paris
_______________________________________________
developers mailing list
developers at lists.quantum-espresso.org<mailto:developers at lists.quantum-espresso.org>
https://lists.quantum-espresso.org/mailman/listinfo/developers




_______________________________________________
developers mailing list
developers at lists.quantum-espresso.org<mailto:developers at lists.quantum-espresso.org>
https://lists.quantum-espresso.org/mailman/listinfo/developers


_______________________________________________
developers mailing list
developers at lists.quantum-espresso.org<mailto:developers at lists.quantum-espresso.org>
https://lists.quantum-espresso.org/mailman/listinfo/developers

_______________________________________________
developers mailing list
developers at lists.quantum-espresso.org<mailto:developers at lists.quantum-espresso.org>
https://lists.quantum-espresso.org/mailman/listinfo/developers

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/developers/attachments/20200522/0165ddfb/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pwscf.in
Type: application/octet-stream
Size: 1438 bytes
Desc: pwscf.in
URL: <http://lists.quantum-espresso.org/pipermail/developers/attachments/20200522/0165ddfb/attachment-0002.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pwscf.out.afm
Type: application/octet-stream
Size: 188537 bytes
Desc: pwscf.out.afm
URL: <http://lists.quantum-espresso.org/pipermail/developers/attachments/20200522/0165ddfb/attachment-0003.obj>