[Pw_forum] overlap of atoms

[Payam Norouzzadeh]

Hello Espresso users

I want to relax the given structure in below that is a Clathrate with BCC
structure and 54 atoms. I am getting errors about overlap of atoms.
As Dr.Lorenzo Paulatto mentioned if I apply the basis vector a/2*(1,1,1) of
the bcc lattice I notice that some atoms overlap each other (1 and 5,2 and 6
,....).
I am sure that the positions are correct and I used other softwares like
ABINIT and VASP and got relaxed structures without trouble. Likely I should
stop  checking the symmetry of structure.Does any one know how can I do
that?

This is my input file:

&CONTROL
                       title = Ba ,
                 calculation = 'relax' ,
                restart_mode = 'from_scratch' ,
                  wf_collect = .true. ,
                      outdir = '/lustre/work/pnorouzz/espresso//Ba/relax' ,
                      wfcdir = '/lustre/work/pnorouzz/espresso/Ba/relax' ,
                  pseudo_dir = '/lustre/work/pnorouzz/espresso//Ba/relax' ,
                          dt = 20 ,
 /
 &SYSTEM
                     ibrav =  3,
                     celldm(1) = 22,
                     nat = 54,
                     ntyp = 3,
                     ecutwfc = 50 ,
                     ecutrho = 500 ,
 /
 &ELECTRONS
                    conv_thr = 1.D-8 ,
                 mixing_beta = 0.5D0 ,
 /
 &IONS
                ion_dynamics = 'damp' ,
           pot_extrapolation = 'second_order' ,
           wfc_extrapolation = 'second_order' ,
                     upscale = 100 ,
 /
ATOMIC_SPECIES
   Ba   137.327    Ba.pw91-nsp-van.UPF
   Sn   118.710    Sn.pw91-n-van.UPF
   Ga   71.0843639 Ga.pw91-n-van.UPF
ATOMIC_POSITIONS
Ba 0.186 0.186 0.186
Ba 0.814 0.814 0.186
Ba 0.814 0.186 0.814
Ba 0.186 0.814 0.814
Ba 0.686 0.686 0.686
Ba 0.314 0.314 0.686
Ba 0.314 0.686 0.314
Ba 0.686 0.314 0.314
Sn 0 0 0
Sn 0.5 0.5 0.5
Sn 0.6348 0.6348 0.3652
Sn 0.3652 0.6348 0.6348
Sn 0.1348 0.1348 0.8652
Sn 0.8652 0.1348 0.1348
Sn 0.41596 0.41596 0.1441
Sn 0.58404 0.58404 0.1441
Sn 0.58404 0.41596 0.8559
Sn 0.41596 0.58404 0.8559
Sn 0.1441 0.41596 0.41596
Sn 0.8559 0.41596 0.58404
Sn 0.41596 0.1441 0.41596
Sn 0.58404 0.1441 0.58404
Sn 0.91596 0.91596 0.6441
Sn 0.08404 0.08404 0.6441
Sn 0.08404 0.91596 0.3559
Sn 0.91596 0.08404 0.3559
Sn 0.6441 0.91596 0.91596
Sn 0.3559 0.91596 0.08404
Sn 0.91596 0.6441 0.91596
Sn 0.08404 0.6441 0.08404
Sn 0.91596 0.3559 0.08404
Sn 0.08404 0.3559 0.91596
Sn 0 0.25 0.5
Sn 0 0.75 0.5
Sn 0.5 0 0.25
Sn 0.5 0 0.75
Sn 0 0.5 0.25
Sn 0 0.5 0.75
Ga 0.3652 0.3652 0.3652
Ga 0.6348 0.3652 0.6348
Ga 0.8652 0.8652 0.8652
Ga 0.1348 0.8652 0.1348
Ga 0.1441 0.58404 0.58404
Ga 0.8559 0.58404 0.41596
Ga 0.41596 0.8559 0.58404
Ga 0.58404 0.8559 0.41596
Ga 0.6441 0.08404 0.08404
Ga 0.3559 0.08404 0.91596
Ga 0.25 0.5 0
Ga 0.75 0.5 0
Ga 0.5 0.25 0
Ga 0.5 0.75 0
Ga 0.25 0 0.5
Ga 0.75 0 0.5
K_POINTS automatic
4 4 4  0 0 0

Best regards,Payam Norouzzadeh
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