The ABINIT Users Mailing List ( CLOSED )

["D. R. Hamann" <drhamann@mat-simresearch.com>]

Dear Xenophon,

This is a feature -- not an error.  Your shiftk set is wrong for fcc.  
Look at the input file for exercise 6 of the tutorial on elastic 
properties.  Alternatively, you can use nshiftk 1, shiftk 0 0 0, and a 
bigger ngkpt set for comparable convergence.

Don  Hamann

xenophon.krokidis@scienomics.com wrote:
> Dear All,
>
> I am using the input below to compute elastic properties but I get the
> following error message when the 3rd dataset is executed (note that if I use
> nshiftk = 1 and shiftk 0.0 0.0 0.0 I don't get this error).
>
> Thak you for the help.
>
> Xenophon
>
>   
> > > > > > 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.
>
>  leave_new : decision taken to exit ...
>
>   
> > > > > > INPUT<<<<<
> > > > > >             
>
> # Diamond
>  acell 3.5668 3.5668 3.5668 Angstr
>  rprim 0.0  0.5  0.5
>        0.5  0.0  0.5
>        0.5  0.5  0.0
>  chkprim 0
>  ecut 150.0 eV
>  ecutsm 13.6057 eV
>  iscf 5
>  nkpt 0
>  kptopt 1
>  ngkpt 4 4 4
>  nshiftk 4
>  shiftk 0.500000 0.500000 0.500000
>         0.500000 0.000000 0.000000
>         0.000000 0.500000 0.500000
>         0.000000 0.000000 0.500000
>  nstep 50
>  ixc 1
>  nband  6
>  nsppol 1
>  natom 2
>  natrd 2
>  ntypat 1
>  occopt 1
>  prtden 1
>  typat 1 1
>  xred 0 0 0
>  0.25 0.25 0.25
>  znucl 6
>
>  # Calculation of elastic constants
>  iscf1      5
>  kptopt1    1
>  tolvrs1    1.0d-18
>
>  getwfk2   -1
>  iscf2     -3
>  kptopt2    2
>  nqpt2      1
>  qpt2       0.0 0.0 0.0
>  rfelfd2    2
>  rfdir2     1 1 1
>  tolwfr2    1.0d-20
>
>  getddk3   -1
>  getwfk3   -2
>  iscf3      5
>  kptopt3    2
>  nqpt3      1
>  qpt3       0.0 0.0 0.0
>  rfphon3    1
>  rfatpol3   1 2
>  rfstrs3    3
>  rfdir3     1 1 1
>  tolvrs3    1.0d-10
>  ndtset 3
>
>   

--
D. R. Hamann
Mat-Sim Research LLC    | Department of Physics
P.O. Box 742            |  and Astronomy
Murray Hill, NJ 07974   | Rutgers University
phone: 908-370-8079     | 732-445-5500, x4381

email: drhamann@mat-simresearch.com