[Pw_forum] How to set variables when get symmetry operation # N not allowed?
Arena Konta
qe6user at gmail.com
Thu Feb 8 17:30:41 CET 2018
Dear prof. Paolo Giannozzi
Thank you for quick response. Please, clarify me: I set variable
"use_all_frac=.true." and option "verbosity='high'" and get output showed
below. Hoverwer, I am still unable to find the right values of frac. trans
(n=1?) I have to calculate phonons,
so i need to set right k-mesh.
8 Sym. Ops., with inversion, found
s frac. trans.
isym = 1 identity
cryst. s( 1) = ( 1 0 0 )
( 0 1 0 )
( 0 0 1 )
cart. s( 1) = ( 1.0000000 0.0000000 0.0000000 )
( 0.0000000 1.0000000 0.0000000 )
( 0.0000000 0.0000000 1.0000000 )
isym = 2 180 deg rotation - cart. axis [0,0,1]
cryst. s( 2) = ( -1 0 0 )
( 0 -1 0 )
( -1 -1 1 )
cart. s( 2) = ( -1.0000000 0.0000000 0.0000000 )
( 0.0000000 -1.0000000 0.0000000 )
( 0.0000000 0.0000000 1.0000000 )
isym = 3 90 deg rotation - cart. axis [0,0,-1]
cryst. s( 3) = ( 0 -1 0 )
( 1 0 0 )
( 0 -1 1 )
cart. s( 3) = ( 0.0000000 1.0000000 0.0000000 )
( -1.0000000 0.0000000 0.0000000 )
( 0.0000000 0.0000000 1.0000000 )
isym = 4 90 deg rotation - cart. axis [0,0,1]
cryst. s( 4) = ( 0 1 0 )
( -1 0 0 )
( -1 0 1 )
cart. s( 4) = ( 0.0000000 -1.0000000 0.0000000 )
( 1.0000000 0.0000000 0.0000000 )
( 0.0000000 0.0000000 1.0000000 )
isym = 5 inversion
cryst. s( 5) = ( -1 0 0 )
( 0 -1 0 )
( 0 0 -1 )
cart. s( 5) = ( -1.0000000 0.0000000 0.0000000 )
( 0.0000000 -1.0000000 0.0000000 )
( 0.0000000 0.0000000 -1.0000000 )
isym = 6 inv. 180 deg rotation - cart. axis [0,0,1]
cryst. s( 6) = ( 1 0 0 )
( 0 1 0 )
( 1 1 -1 )
cart. s( 6) = ( 1.0000000 0.0000000 0.0000000 )
( 0.0000000 1.0000000 0.0000000 )
( 0.0000000 0.0000000 -1.0000000 )
isym = 7 inv. 90 deg rotation - cart. axis [0,0,-1]
cryst. s( 7) = ( 0 1 0 )
( -1 0 0 )
( 0 1 -1 )
cart. s( 7) = ( 0.0000000 -1.0000000 0.0000000 )
( 1.0000000 0.0000000 0.0000000 )
( 0.0000000 0.0000000 -1.0000000 )
isym = 8 inv. 90 deg rotation - cart. axis [0,0,1]
cryst. s( 8) = ( 0 -1 0 )
( 1 0 0 )
( 1 0 -1 )
cart. s( 8) = ( 0.0000000 1.0000000 0.0000000 )
( -1.0000000 0.0000000 0.0000000 )
( 0.0000000 0.0000000 -1.0000000 )
Thank you in avdance.
Arena Konta
*****************************************************************************
Set variable "use_all_frac=.true." and option "verbosity='high'". This will
find and print all symmetries and associated fractional translations. If a
fractional translation along a crystal axis is 1/n, with n integer, the FFT
dimension along that axis must contain a factor n. If you do not need
hybrid functionals or phonons, just set variable "use_all_frac=.true."
Paolo
2018-02-07 20:18 GMT+01:00 Arena Konta <qe6user at gmail.com>:
> Hi All,
>
> I read Troubleshooting and found out that "you can force your FFT grid to be commensurate with fractional translation (set variables nr1, nr2, nr3 to suitable values)". How to do this for the crystal structure presented below? I have tried to this for various k-mesh, but every time I get 6 symmetry operations are not compatible with FFT grid:
> warning: symmetry operation # 2 not compatible with FFT grid.
> -1 0 0
> 0 -1 0
> -1 -1 1
> warning: symmetry operation # 3 not compatible with FFT grid.
> 0 -1 0
> 1 0 0
> 0 -1 1
> warning: symmetry operation # 4 not compatible with FFT grid.
> 0 1 0
> -1 0 0
> -1 0 1
> warning: symmetry operation # 6 not compatible with FFT grid.
> 1 0 0
> 0 1 0
> 1 1 -1
> warning: symmetry operation # 7 not compatible with FFT grid.
> 0 1 0
> -1 0 0
> 0 1 -1
> warning: symmetry operation # 8 not compatible with FFT grid.
> 0 -1 0
> 1 0 0
> 1 0 -1
>
> &SYSTEM
> ibrav = 0
> celldm(1) = 18.61847
> nat = 9
> ntyp = 2
> /
> CELL_PARAMETERS {alat}
> 1.000000000000000 0.000000000000000 0.000000000000000
> 0.000000000000000 1.000000000000000 0.000000000000000
> 0.500000000000000 0.500000000000000 0.175193124160743
>
> ATOMIC_POSITIONS {crystal}
> A 0.304370000000000 0.373120000000000 0.000000000000000
> A 0.626880000000000 0.304370000000000 0.000000000000000
> A 0.695630000000000 0.626880000000000 0.000000000000000
> A 0.373120000000000 0.695630000000000 0.000000000000000
> A 0.000000000000000 0.000000000000000 0.000000000000000
> B 0.055910000000000 0.282920000000000 0.000000000000000
> B 0.717080000000000 0.055910000000000 0.000000000000000
> B 0.944090000000000 0.717080000000000 0.000000000000000
> B 0.282920000000000 0.944090000000000 0.000000000000000
>
> K_POINTS automatic
> 10 10 18 0 0 0
>
>
>
> --
> with regards
>
> Arena Konta
> The Institute of Thermophysics in Novosibirsk Scientific Center
>
>
--
with regards
Arena Konta
The Institute of Thermophysics in Novosibirsk Scientific Center
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