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[PGanesh <pganesh@ciw.edu>]

Hi,

I am computing electric-field and strain perturbations for a 20 atom 
cell with space group Fm-3m at q=(0,0,0)  ( I am using version 5.4.4).  
I have already computed the phonon perturbations successfully.  I get 
the following error :

symkchk : found identity, with number  1
symkchk : ERROR -
  k-point set must have full space-group symmetry
  there is no match for kpt   1 transformed by symmetry   3
  Action : change kptopt to 2 or 3 and/or change or use shiftk
           shiftk = 0 0 0 is always a safe choice.


My kptopt is 2.  I changed it to 3, but still get the same error.  I am 
afraid that if I use the other option of using shiftk=0 0 0, then the I 
won't be able to merge it with the database of phonon calculations which 
were done with shift 0.5 0.5 0.5.  I have two questions:

1> Why am I getting this error for electric-field and strain 
perturbations, while I didnt get it for phonon pertirbations (i.e. when 
rfphon =1 )
2> Is there a way to get around the problem, so that I don't have to 
recalculate the phonon perturbations at q=0 0 0 ?

Thanks,
Ganesh