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Negative value in CHGCAR for Si bulk scf calculation

Posted: Tue Jun 01, 2010 3:36 pm
by brsahu
Dear VASP users and head administrator

I have a 2 atom Si in bulk diamond structure. I used VASP5.2 (and
VASP4.6) for self-consistent run and got the CHGCAR file. I checked
the CHGCAR file it has many negative values of total charge density
which is unphysical.

My system is bulk without any vacuum. I checked VASP FAQ's in the manual
but mainly it talks about unphysical negative charge when vacuum is present.

My INCAR file looks like this:
I post 3 different INCAR files showing negative charge in CHGCAR

-1st

ISTART = 0
ICHARG = 2
PREC = medium

ISMEAR = 1
EDIFF = 1E-04 stopping-criterion for ELM

-2nd

ISTART = 0
ICHARG = 2
PREC = medium

ISMEAR = 0
EDIFF = 1E-04 stopping-criterion for ELM

-3rd
ISTART = 0
ICHARG = 2
INIWAV = 1
ISPIN = 1
PREC = high

NELM = 100
NELMIN = 5
EDIFF = 1E-05 stopping-criterion for ELM
ENCUT = 340.0000

ISYM = 0
ADDGRID = T
ISMEAR = -5
IALGO = 48
LREAL = .FALSE.

GGA_COMPAT = .FALSE. #faster calc
SYMPREC = 1E-06 #to remove "found some non integer element in rotn matrix" error

NGXF= 90
NGYF= 90
NGZF= 90



Pl. let me know if any additional info related to this is needed.

--Sahu

Re: Negative value in CHGCAR for Si bulk scf calculation

Posted: Wed Sep 11, 2024 2:24 pm
by support_vasp

Hi,

We're sorry that we didn’t answer your question. This does not live up to the quality of support that we aim to provide. The team has since expanded. If we can still help with your problem, please ask again in a new post, linking to this one, and we will answer as quickly as possible.

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