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Dear all,

My system has 348 electrons and 190 bands (only 1 k-point) and I'm trying to constrain the occupancies of the orbitals by using FERWE and FERDO tags. The problem is that VASP (version 4.6) gives the Error:

vasp.4.6.35 3Apr08 gamma-only
POSCAR found : 3 types and 90 ions
LDA part: xc-table for Ceperly-Alder, standard interpolation
POSCAR, INCAR and KPOINTS ok, starting setup
WARNING: wrap around errors must be expected
FFT: planning ... 1
reading WAVECAR
Error reading item 'FERWE' from file INCAR.


I tried different sintaxes (as was discussed earlier in this forum), but the error still persists. One variant is explicit:
ISMEAR = -2
NBANDS = 190
ISPIN = 2
FERWE = 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
FERDO = 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

The other, more compact one:
ISMEAR = -2
NBANDS = 190
ISPIN = 2
FERWE = 173*1 1 0 15*0
FERDO = 173*1 0 1 15*0

Both variants lead to that error.

I also tried smaller system (carbon atom with only 8 bands, as was suggested on this forum) - that smaller problem worked well.

How should I specify my input for such bigger system so the vasp would understand all correctly?

Thank you in advance!

Usually I use real number to indicate the occupation. In your second option, should it read (?):

FERWE = 174*1.00 16*0
FERDO = 173*1.00 1*0.00 1*1.00 15*0.00

Hope it works.

When using long lines keep in mind that the length of the line is limited to 255 characters. Cf. the discussion to long lines:
http://cms.mpi.univie.ac.at/vasp-forum/ ... .php?3.833
Compact writing of FERWE and FERDO as suggested above (both integer and real) should work.