I don't think you need to specify "ibrav" (the code should selecvt the
proper one), but you need to specify celldm(2) and celldm(3).

Paolo

On Thu, Oct 13, 2016 at 2:39 PM, Tsung-Lung Li <quan...@mail.ncyu.edu.tw>
wrote:

> Dear QE Friends:
>
> I encounter a problem with the space_group option. A part of my QE input is
> attached at the end of this message.
>
> The crystal I am working on has symmetry "C 1 2/c 1" (as suggested by the
> cif file from which I take the structure data).
>
> Suggested by the following two webpages, I set "space_group = 15".
> http://www.cryst.ehu.es/cgi-bin/cryst/programs/nph-wp-list?gnum=15&gua=b
> http://img.chem.ucl.ac.uk/sgp/large/015ay1.htm
>
> Because the unique axis is along b in my problem,
> I take "ibrav = -12" (monoclinic).
>
> Running QE, I got the following error message.
>
>       Error in routine input (1):
>       Input ibrav not compatible with space group number
>
> There is not much information about space_group option in QE manual.
> Could ould you please point out what is wrong with the input?
>
> Thbak you.
>
> Tsung-Lung Li
>
> ---------------------------------------------------
> &system
>    ibrav = -12
>    celldm(1) = 11.86181088389489 ! bohr
>    ntyp = 4
>    nat = 7
>    space_group = 15
>    uniqueb = .true.
>    origin_choice = 1
>    ....
> /
>
> ATOMIC_SPECIES
>     Ca   40.0780000000  Ca_pbe_v1.uspp.F.UPF
>      S   32.0650000000  S_pbe_v1.2.uspp.F.UPF
>      O   15.9994000000  O.pbe-n-kjpaw_psl.0.1.UPF
>      H    1.0079000000  H.pbe-rrkjus_psl.0.1.UPF
>
> ATOMIC_POSITIONS crystal_sg
>    Ca  0.00000   0.17050   0.25000
>    S   0.00000   0.32727   0.75000
>    O   0.08319   0.27218   0.59103
>    O   0.19997   0.38195   0.91298
>    O  -0.20823   0.06826  -0.07831
>    H  -0.25800   0.08700  -0.23400
>    H  -0.24400   0.02000  -0.07700
>
> --
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>



-- 
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222
_______________________________________________
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Reply via email to