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hi all

i am studying lanthanum using a simple cubic unit cell. The potential used is poppaw_LDA

INCAR file is as
System=lanthanum
NWRITE=2
ISTART=0
ICHARGE=2
PREC =low
EDIFF = 10E-2
ENCUT=340
ISMEAR=-1
IPAR=1
SIGMA=0.1

POSCAR is
lanthanum
4.1565
1.000 0.000 0.000
0.000 1.000 0.000
0.000 0.000 1.000
7
cartesian
0.0 0.0 0.0
0.5 0.5 0.1996
0.5 0.5 0.8004
0.5 0.1996 0.5
0.5 0.8004 0.5
0.1996 0.5 0.5
0.8004 0.5 0.5


when i tried to compile it i got



LDA part: xc-table for Ceperly-Alder, standard interpolation

-----------------------------------------------------------------------------
| |
| W W AA RRRRR N N II N N GGGG !!! |
| W W A A R R NN N II NN N G G !!! |
| W W A A R R N N N II N N N G !!! |
| W WW W AAAAAA RRRRR N N N II N N N G GGG ! |
| WW WW A A R R N NN II N NN G G |
| W W A A R R N N II N N GGGG !!! |
| |
| The distance between some ions is very small |
| please check the nearest neigbor list in the OUTCAR file |
| I HOPE YOU KNOW, WHAT YOU ARE DOING |
| |
-----------------------------------------------------------------------------

POSCAR, INCAR and KPOINTS ok, starting setup
FFT: planning ... 1
reading WAVECAR
entering main loop
N E dE d eps ncg rms rms(c)
DAV: 1 0.125734203289E+04 0.12573E+04 -0.17965E+04 100 0.225E+03
DAV: 2 0.503992434661E+03 -0.75335E+03 -0.72333E+03 170 0.738E+02
DAV: 3 0.176807476389E+03 -0.32718E+03 -0.32227E+03 168 0.493E+02
DAV: 4 0.981903061141E+02 -0.78617E+02 -0.76575E+02 154 0.272E+02
hit a member that was already found in another star
hit a member that was already found in another star
hit a member that was already found in another star
hit a member that was already found in another star
hit a member that was already found in another star


what is the meaning of this message. Please help

thanks in advance

please check the geometry of your system. btw doesn't La have a dhcp unitcell ?
use for example VESTA to visualize your geometry...the moment that is fixed the k-point error will probably disappear

Danny

I don't have much experience with this "hit a member" issue, but setting ISYM = 0 should eliminate the problem. Alternatively check whether or not the relations between the NGX, NGY and NGZ values are correct and set them manually in the INCAR file if they are not. It seemed to help the colleague in this thread:

http://cms.mpi.univie.ac.at/vasp-forum/ ... php?3.3135

Cheers,
/Dan



<span class='smallblacktext'>[ Edited Mon May 03 2010, 09:52PM ]</span>

The very first warning/error is the one to eliminate first. VASP complains about small distances, so there you go first. The "star" probably disappears after the distance stuff is resolved.

cheers,

alex

Like Danny said, I think this is a geometry issue. For Fm3(bar)m, I get the following POSCAR:

La
1.0
5.29600000 0.00000000 0.00000000
0.00000000 5.29600000 0.00000000
0.00000000 0.00000000 5.29600000
4
cart
0.00000000 0.00000000 0.00000000
0.00000000 2.64800000 2.64800000
2.64800000 0.00000000 2.64800000
2.64800000 2.64800000 0.00000000

For P63/mmc I get the following for POSCAR:

La
1.0
3.75000000 0.00000000 0.00000000
-1.87500000 3.24759526 0.00000000
0.00000000 0.00000000 6.07000000
2
cart
0.00000000 2.16506351 1.51750000
1.87500000 1.08253175 4.55250000

I got the cif files from http://www.crystallography.net/search.html and opened them in agui viewer. Can you try running your calculation again with these POSCAR files?

Thanks