The ABINIT Users Mailing List ( CLOSED )

[Xavier Gonze <gonze@pcpm.ucl.ac.be>]

Dear Tieyu Lu,

The list of nuclei coordinates that you give does not have the  
symmetry of spacegroup 33.
I bet that the number of nuclei in the primitive cell is not 7  :  
this number
corresponds likely to the coordinates of nuclei present only in the  
*irreducible* part of the primitive cell.
Supposing the number of nuclei in the primitive cell is 28 (just to  
fix the idea !),
then you should have :
natom 28
natrd 7
And ABINIT will generate all the other atomic positions automatically.

Now, pay also attention to the different possible settings of the  
cell, in case of the
space group 33. Have a look at
http://www.abinit.org/Infos_v5.2/users/spacegrouphelpfile.html

Xavier

On 10 Dec 2006, at 07:44, mailoliver@163.com wrote:

> Dear all:
>
> I try to calculate BaAlH5 by abinit code. But there are some errors  
> of symmetry. The atomic coordinates and the space group number  
> agree with other people works(published in PRB).
>
> please give me some advice.
>
> best wish
>
> tieyu lu
>
> my input:::
> *********************
> xred
> 0.687 0.156 0.250
> 0.049 0.847 0.233
> 0.006 0.939 0.919
> 0.576 0.846 0.019
> 0.572 0.805 0.497
> 0.353 0.697 0.240
> 0.711 0.541 0.209
> ionmov  2
> ntime  9999
> tolmxf 5.0d-4
> optcell 2
> ecutsm 0.5
> dilatmx 1.2
> acell 17.3734 13.3036 9.6487    # The keyword "acell" refers to the
>                   # lengths of the primitive vectors (in Bohr)
> rprim  1 0 0   # FCC primitive vectors (to be scaled by acell)
>        0 1 0
>        0 0 1
> ntypat 3          # There is only one type of atom
> znucl 56 13 1           # The keyword "znucl" refers to the atomic  
> number of the
> natom 7           # There are two atoms
> typat  1 2 3 3 3 3 3       # They both are of type 1, that is,  
> Hydrogen
> ecut 20.0         # Maximal kinetic energy cut-off, in Hartree
> kptopt 1
> ngkpt   4 5 8
> nshiftk 1
> shiftk  0. 0. 0.  # These shifts will be the same for all grids
> nstep 9999          # Maximal number of SCF cycles
> toldfe 1.0d-6     # Will stop when, twice in a row, the difference
> diemac 12.0        # Although this is not mandatory, it is worth to
> diemix 0.5        # function used as the standard preconditioner
> prtwf 0
> spgroup 33
> ****************************
>
>
> part of log::
> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>  symatm: atom number    1 is reached starting at atom
>    1  1  1  1
>  symatm: atom number    2 is reached starting at atom
>    2  2  2  2
>  symatm: atom number    3 is reached starting at atom
>    3  3  4  5
>  symatm: atom number    4 is reached starting at atom
>    4  5  3  7
>  symatm: atom number    5 is reached starting at atom
>    5  4  6  3
>  symatm: atom number    6 is reached starting at atom
>    6  7  7  3
>  symatm: atom number    7 is reached starting at atom
>    7  6  6  3
>  symatm: maximum (delta t)=   5.00000E-01 is larger than tol=   
> 1.0000E-08
>
>  symatm : ERROR -
>   Largest error (above) is so large that either input  atomic  
> coordinates (xred)
>   are wrong or space group symmetry data is wrong.
>   Action : correct your input file.
>
>  leave_new : decision taken to exit ...