VBM/CBM decomposed charge density

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neha_kapila
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VBM/CBM decomposed charge density

#1 Post by neha_kapila » Wed Mar 03, 2021 5:13 am

Dear all,
I am trying to find out band decomposed charge density for VBM and CBM for TMDC hetrostructure. Can anyone help me.

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Re: VBM/CBM decomposed charge density

#2 Post by neha_kapila » Sun Mar 07, 2021 8:07 am

Dear all,I am trying to plot band decomposed charge density for hetrostructure of MoS2/Ws2 system.The charge density for VBM and CBM as plotted in the following paper.
SYSTEM = MoS2/WS2
ISTART = 1
ISPIN = 2
ICHARG = 11
ISMEAR = -5 ! Tetrahedron
ENCUT = 400
PREC = Accurate
IVDW = 1
IBRION = -1
NSW = 0
EDIFF = 0.000001
EDIFFG = -0.001
LCHARG = .TRUE.
LPARD = .TRUE.
IBAND = 17 18 19 20
LSEPB = .TRUE.
KPUSE = 1 2 3 4
I am sharing my input as well as the Band decomposed charge density as I have plotted,please suggest me what is wrong here?
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Re: VBM/CBM decomposed charge density

#3 Post by SKM » Sun Mar 19, 2023 3:19 am

Hi all / Admin
1. Which are the key INCAR tags, that are essential for getting VBM, and CBM decomposed charge density?

2. In case if not used these key-tags but completed the run, but now i want to get this data of charge density of VBM and CBM, Do i need to re-run entire computation or can I do a single point run, with these additional INCAR Tags?

Can anyone suggest?

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Re: VBM/CBM decomposed charge density

#4 Post by henrique_miranda » Wed Mar 22, 2023 1:40 pm

You can find information about the band decomposed charge densities here
https://www.vasp.at/wiki/index.php/Band ... _densities

If you already run the calculation and did not have these tags set in your INCAR file you can do a non-self-consistent calculation (single point run) afterwards with these tags added.

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Re: VBM/CBM decomposed charge density

#5 Post by SKM » Sun Mar 26, 2023 10:41 am

Thank you for the reply.

OK.then i use LPARD, and IBAND, and may be LSEPB rest of the tags might not be important for me, i suppose. But because i only want VBM and CBM charge densities, how do i know which band numbers correspond to this two VBM and CBM?
Do i need to get this bands from any previous runs, (say. during optimisation? or normal dos plot runs?) to check which k-point band Nos has full occupancy and which has zero occupancy?
and also i checked my previous runs, i did not use these tags before.

Also unfortunately the WAVECAR files were deleted to save space, as i was taking back-up. In such a case, if i re-run one single point run using tags related to both partial density band tags LPARD, IBAND, LSEPB and LWAVE=true, same time?
OR
I must first i generate WAVECAR with a single-point run, and then another single point run with partial density tags?

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Re: VBM/CBM decomposed charge density

#6 Post by henrique_miranda » Mon Mar 27, 2023 6:43 am

You can check at which band and k-point the VBM and CBM are by inspecting the OUTCAR file.

If you don't have a WAVECAR from a previous run then just add these tags to your INCAR file and re-run the calculation.

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