[Pw_forum] setup error

[Stefano de Gironcoli]

As the error message states, the system is a metal since nelec=3 is odd
and it is not possible to use fixed occupations (that is to fully occupy
the lowest nelec/2 bands).
You should provide information on how you want to treat Fermi energy
crossings.

occupations='smearing' or 'tethrahedra' are possible choices,
occupations='fixed' can only be applied to insulators with a gap.

If you choose the smearing option you need to provide also (in the
&SYSTEM namelist)
1) the smearing type:
smearing='gaussian','methfessel-paxton','marzari-vanderbilt', of
'fermi-dirac'
2) the smearing width: degauss= xx in Rydberg energy units.
If you choose the tetrahedra option you need to use automatically
generated uniform k-point grids.

Please read information in file pwdocs/INPUT_PW regarding these variables.

Stefano de Gironcoli

ma Yanming wrote:

>
> Dear Users,
>
> I tried to run scf calculation in my Boron case (space group R-3m;
> a=b=c, alpha=58.02)
> The following is my input:
>
> cat > B.scf.in<< EOF
> B
> Rhom
> &CONTROL
> calculation='scf', tstress=.t.,tprnfor=.t.,
> PSEUDO_DIR = '$HOME/yanming/pwwork/pseudo/',
> outdir = '/scratch/B/B_Rho/',
> /
> &SYSTEM
> ibrav= 5, celldm(1) =9.6, celldm(4)=0.529031,
> nat= 1, ntyp= 1,
> occupations='fixed',
> ecutwfc =30.0,
> /
> &ELECTRONS mixing_beta = 0.7,
> conv_thr = 1.0d-8,
> /
> ATOMIC_SPECIES
> B 10.811 B.pz-vbc.UPF
> ATOMIC_POSITIONS {crystal}
> B 0.0 0.0 0.0
> K_POINTS{automatic}
> 8 8 8 0 0 0
> EOF
>
> The error message is the following:
>
> Writing file pwscf.save from setup : error # 1 the crystal is a metal
> stopping ...
> file written
> from setup : error # 1
> the crystal is a metal
> stopping ...
> %%%%%%%%%%%%%%%%%%%%%%
> from setup : error # 1 the crystal is a metal
> %%%%%%%%%%%%%%%%%%%%%%
> stopping ...
>
>
> Any comments on this error?
> Thanks in advance.
>
> Yanming Ma PhD
> Steacie Institute for Molecular Sciences,
> National Research Councils of Canada.
> 100 Sussex
> K1A 0R6
>
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