[Wien] AFM supercell

[Roberto Iglesias]

Dear Gerhard
Thank you for your reply. Yes, I originally did 
that and it works fine. However, I wanted to 
check if it was possible to run the same thing 
for a 2x2x2 supercell, for instance.
Would the two atoms in the P m-3m cell have the 
same magnetic moment values as the 8 pairs in the 
supercell? If that would be the case, I'd simply 
forget about running the 16 atom case.

Best regards

Roberto

At 09:59 20/03/2009, you wrote:

>Why don't you just use P m-3m with the center 
>atom at 1/2 1/2 1/2 having reversed spin ?
>
>Ciao
>Gerhard
>
>====================================
>Dr. Gerhard H. Fecher
>Institut of Inorganic and Analytical Chemistry
>Johannes Gutenberg - University
>55099 Mainz
>________________________________________
>Von: wien-bounces at zeus.theochem.tuwien.ac.at 
>[wien-bounces at zeus.theochem.tuwien.ac.at] im 
>Auftrag von ROBERTO LUIS IGLESIAS PASTRANA [roberto at uniovi.es]
>Gesendet: Freitag, 20. März 2009 09:53
>An: WIEN2k Mailing List
>Betreff: [Wien] AFM supercell
>
>Dear all
>
>I'm trying to run an AFM calculation in a 16 
>atom Cr supercell. I want to have the Cr 
>magnetic moment values for reference purposes, 
>in order to compare to other systems of the same 
>size and later larger ones. The normal bcc unit 
>cell AFM calculation runs fine, following the 
>procedures outlined in the UG, section 4.5.4, 
>and I get the same magnetic moments for both Cr 
>atoms in the cell but with different signs.
>  I set up a 16 atom supercell and then flip the 
> spins of the Cr atoms in consecutive pairs in 
> case.inst. I also tried to flip just the second 
> 8 atoms, unphysical as it may be, and 
> consequently there is a crash in dstart. When I 
> perform either a runsp_lapw or a runafm_lapw 
> calculation I always get zero, or close to zero 
> magnetic moments in all sixteen Cr atoms, as if 
> the system was in a nonmagnetic state. The 
> question is: What else do I need to do in order 
> to get final magnetic moments with the same 
> absolute values but with alternate different 
> signs, as for the bcc unit cell? Or am I writing nonsense?
>I'm using WIEN2k_08.3 and running in 8 processors via k-point parallelization.
>
>Thanks in advance
>
>Roberto
>
>---------------------------------------
>Roberto Iglesias
>Physics Department
>University of Oviedo
>Calvo Sotelo, s/n
>33007 Oviedo
>SPAIN
>Tel: +34985102898
>Fax: +34985103324
>email: roberto at uniovi.es
>---------------------------------------
>
>--------------------------------------
>_______________________________________________
>Wien mailing list
>Wien at zeus.theochem.tuwien.ac.at
>http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>_______________________________________________
>Wien mailing list
>Wien at zeus.theochem.tuwien.ac.at
>http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien

Roberto Iglesias Pastrana
Departamento de Física
Universidad de Oviedo
C/ Calvo Sotelo, s/n 33007 Oviedo
Tel.: +34 985102898
         +34 985458136
Fax: +34 985103324
e-mail: roberto at uniovi.es
          
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20090320/65a9b4bc/attachment.html