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["lvying" <lvying@ctb.pku.edu.cn>]

Hi:    
    I have runned the Test files on GW, which generated a _KSS file with the 
same name in the ZnO run, so the code can read the _KSS file, but a 
completely wrong one.

    Thank  you very much !

----- Original Message ----- 
From: "Valerio Olevano" <valerio.olevano@polytechnique.fr>
To: <forum@abinit.org>
Sent: Wednesday, July 09, 2003 7:35 PM
Subject: [abinit-forum] Re: GW calculation: inversion and non-symmorphyc 
symmetries


> Dear lvying,
> 
> I carefull read your log and out files.
> there is something obscure as the the second dataset does not generate 
> the KSS file
> but the dataset 3 is able to read a KSS generated by the previous 
> dataset.
> 
> But however, the next is general concerning the subject
> "inversion and non-symmorphyc symmetries" in GW:
> 
> If the system possesses or not the spatial inversion symmetry is not 
> important.
> The Warning
>   The inversion was not found in the symmetries list.
>   - outstat - WARNING:
>     GW prog. may give incorrect results !!
> given so far has been removed in the new versions as we checked, we are 
> sure the results
> are good.
> 
> If the parity (spatial inversion symmetry) is present, it is eliminated 
> when generating the KSS file
> since the GW code treats at its place a time reversal symmetry (which 
> is owned for sure by all the physical
> systems). This to save time and also for another reason that will be 
> clear in the following.
> 
> The GW code is not able to treat so far the non-symmorphyc symmetries, 
> i.e. symmetries
> associated to nonzero traslations (tnons).
> So that you must pay attetention in the log file (as in yours) to 
> errors of this type:
>   - outstat - ERROR:
>     Non-symmorphic operations still remain in the symmetries list
>     Program does not stop but _KSS file will not be created...
> 
> When removing the inversion symmetry (and the set of symmetries which 
> are the product
> of a rotation times the inversion) the code has the chance to remove 
> all the non-symmorphic
> symmetries. So that we rest with only symmorphic symmetries.
> 
> If not, you should remove by hand the non-syymorphic symmetries.
> set in the input file
> nsym number_of_the_syymorphic_symmetries
> sym   list_of_syymorphic_symmetries
> 
> In your ZnO case
> nsym 6
> sym
> 1  0  0   0  1  0   0  0  1
> -1  0  0   1  1  0   0  0  1
> 0  1  0  -1 -1  0   0  0  1
> 0 -1  0  -1  0  0   0  0  1
> -1 -1  0   1  0  0   0  0  1
> 1  1  0   0 -1  0   0  0  1
> (check it again, please)
> and good luck!
> 
> V.
>