Negative value in CHGCAR for Si bulk scf calculation

[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

[support_vasp]

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