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Posted: **Thu Sep 28, 2023 10:15 am**

I am working on Van Der Waal Heterostructure of GaSe_ZrS2. I have optimised the system. The pre-processing for bands has also been completed successfully but I am getting a positive value of Fermi Energy. Also when I am performing calculations using VaspKit I am not getting Band.Gap file. Here are the details of my files:

For Relax :

Code: Select all

SYSTEM=GaSe_ZrS2
#Start parameter
ISTART = 0
ICHARG = 1
ISPIN = 1
IVDW = 11
PREC = Normal
NPAR=4

#Electronic Relaxation
NELM=300
ALGO=N
EDIFF=1E-5

#Ionic relaxation
IBRION = 2
NSW = 100
ISIF = 2
POTIM= 0.5
ENCUT = 500


#DOS parameter
ISMEAR = 0
SIGMA = 0.1
NEDOS =4000
LORBIT = 11
#pot
LVHAR = .TRUE.


#dipol
LDIPOL = .TRUE.
IDIPOL = 3
DIPOL = 0.5 0.5 0.5

K points:
1x1x1            this is just a comment-line
 0               0 = automatic generation of k-points
Monkhorst        M use Monkhorst Pack
 8  8  1           grid
 0 0 0           shift (usually 0 0 0)

For SCF :

Code: Select all

SYSTEM=GaSe_ZrS2
#Start parameter
ISTART = 0
ICHARG = 1
ISPIN = 1
IVDW = 11
PREC = Normal
NPAR=4

#Electronic Relaxation
NELM=300
ALGO=N
EDIFF=1E-5

#Ionic relaxation
IBRION = 2
NSW = 0
ISIF = 2
ENCUT = 500


#DOS parameter
ISMEAR = 0
SIGMA = 0.1
NEDOS =4000
LORBIT = 11
#pot
LVHAR = .TRUE.

#dipol
LDIPOL = .TRUE.
IDIPOL = 3
DIPOL = 0.5 0.5 0.5

kpoints:
1x1x1            this is just a comment-line
 0               0 = automatic generation of k-points
Monkhorst        M use Monkhorst Pack
 8  8  1           grid
 0 0 0           shift (usually 0 0 0)

for bands:

Code: Select all

SYSTEM=GaSe_ZrS2
#Start parameter
ISTART = 1
ICHARG = 11
ISPIN = 1
IVDW = 11
LMAXMIX=2
PREC = Normal
NPAR=4

#Electronic Relaxation
NELM=300
ALGO=N
EDIFF=1E-5

#Ionic relaxation
IBRION = 2
NSW = 0
ISIF = 2
ENCUT = 500


#DOS parameter
ISMEAR = 0
SIGMA = 0.1
NEDOS =4000
LORBIT = 11
#pot
LVHAR = .TRUE.

#dipol
LDIPOL = .TRUE.
IDIPOL = 3
DIPOL = 0.5 0.5 0.5

Posted: **Fri Sep 29, 2023 10:17 am**

Hello!

Unfortunately I cannot help you without a complete set of input/output files, please provide them according to the forum posting guidelines, thank you! Also, what exactly do you mean by "positive value of Fermi energy"?

I am sorry but we cannot give any support for third-party software such as VaspKit, please refer to the original authors if there is unexpectedly missing output files.

Best,
Andreas Singraber

Posted: **Mon Oct 02, 2023 1:10 pm**

I am calculating the band structure of Van Der Waal heterostructure Ga Se and ZrS2, First I Optimized the Ga Se/Zrs2 Van Der Waal heterostructure then value of fermi energy is getting positive in OUTCAR file. So i am confused the value of fermi energy should be negative or positive for relaxation or SCF calculation ? And after that whenever i calculating the bands then band.gap file is not generating . I am attaching complete set of my input file and output file.

1.zip

Posted: **Fri Oct 06, 2023 10:03 am**

Hello!

I tried to reproduce your results and noticed that there may be a mismatch in the order of atom types between your POTCAR and POSCAR. In the POSCAR I find

Code: Select all

   Ga   Se   Zr    S
    2     2    1    2

but searching in the POTCAR with (grep " PAW_PBE" POTCAR) I get

Code: Select all

  PAW_PBE Zr_sv 04Jan2005                
  PAW_PBE S 06Sep2000                    
  PAW_PBE Ga 08Apr2002                   
  PAW_PBE Se 06Sep2000

Please note that the order in the POTCAR file determines the order of atomic species, not the Ga Se Zr S line in the POSCAR which is basically just a comment line (have a look at the Wiki pages for POTCAR and POSCAR). So you may have simulated not what you intended to. Can you check again whether there is a mismatch or just the comment line in the POSCAR is wrong?

Best,
Andreas Singraber

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Band.gap file for hetero structure is not generated after post-processing.

Band.gap file for hetero structure is not generated after post-processing.

Re: Band.gap file for hetero structure is not generated after post-processing.

Re: Band.gap file for hetero structure is not generated after post-processing.

Re: Band.gap file for hetero structure is not generated after post-processing.