Removing a Specific electron

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kmkumar · #1 Post by **kmkumar** » Tue Sep 27, 2011 3:29 pm

Dear All

Does any one know is it possible to remove an electron from a specific occupied band in VASP and continue the calculation thereafter.

If so please let me know.

Danny · #2 Post by **Danny** » Wed Sep 28, 2011 1:41 pm

no, you can not.

kmkumar · #3 Post by **kmkumar** » Wed Sep 28, 2011 3:33 pm

How about the FERDO/FERWE tag. It says that we can fix the occupation, but i do not know how it should be used.. Any help

#4 Post by **admin** » Thu Sep 29, 2011 4:05 pm

With FERWE/FERDO you can fix the occupancy of bands. Here is an example for one k-point:
SYSTEM = C atom
ISPIN = 2
NBANDS = 8
ISMEAR = -2 (for input of occupancies from INCAR)
LDIAG = F (keeps the ordering of eigenstates fixed)
FERWE = 3*1 1 0 3*0
FERDO = 3*1 0 1 3*0
Cf. also discussions in another threads.

kmkumar · #5 Post by **kmkumar** » Thu Sep 29, 2011 4:08 pm

I do checked other discussions. Could you please point me to the example of how to use this tag (or understanding its usage). The link you provided in the previous discussion doesn't seem valid.

#6 Post by **admin** » Thu Sep 29, 2011 5:43 pm

Used are 8 bands, spin polarized calculation, alpha electrons occupy four depest bands (FERWE = 11110000), in beta bands one electron is excited (FERDO=11101000). Do the calculation and check the OUTCAR.