[Pw_forum] symmetry of Fe supercell

[Reza Behjatmanesh-Ardakani]

Dear Users
Thank you for answering my previous questions. This question is a
continuation of my previous question, now with clear inputs and outputs of the
calculations.Users who are tired from this
subject can ignore this e-mail. 

I have attached 2 inputs and their outputs of PW.x program. Both of these
inputs belong to the 3*3*3 supercell of Fe pure metal (I have prepared the
graphical structure with the common windows based programs. Then I used
"cif" file and copy the 5 digit coordinations to the QE inputs).  To prepare these inputs I started with
conventional cell (and not primitive ones). Then I built supercell from it. For
the first input, I take the symmetry of "p1" and didn't change it,
but for the second one I searched for the highest symmetry that the supercell
has. I found that it has 229 (Im-3m) space group which is BCC. Then I rebuilt
it according to this symmetry. 54 atoms reduced to only 4. However, the size of
the cell remained unchanged.

Please, see the files, and help me for following questions
:
1- QE contrary to some other codes needs total of atoms in the cell (If I
am right). So, it doesn't produce other positions by 96 symmetry operators of
229 space group. Can I conclud that the results of "fe_229_relax.out"
is not for 3*3*3 supercell, and it may be wrong?

2- I used conventional cell instead of primitive one to produce supercell.
Is it wrong for Quantum-Espresso?

3- Which one should I consider for research: "final energy" or
"per particel energy", which the second is final energy divide to
number of particles.



 
With the Best Regards 

Reza Behjatmanesh-Ardakani 
Associate Professor of Physical Chemistry 
Address: 
Department of Chemistry, 
School of Science, 
Payame Noor University (PNU), 
Ardakan, 
Yazd, 
Iran. 
E-mails: 
1- reza_b_m_a at yahoo.com (preferred), 
2- behjatmanesh at pnu.ac.ir, 
3- reza.b.m.a at gmail.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20131214/5e5feadd/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: fe3_229_relax.in
Type: application/octet-stream
Size: 2037 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20131214/5e5feadd/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: fe3_229_relax.out
Type: application/octet-stream
Size: 50602 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20131214/5e5feadd/attachment-0001.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: fe3_p1_relax.in
Type: application/octet-stream
Size: 5102 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20131214/5e5feadd/attachment-0002.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: fe3_p1_relax.out
Type: application/octet-stream
Size: 36391 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20131214/5e5feadd/attachment-0003.obj>