Questions tagged [vasp]
For questions about use of the Vienna Ab initio Simulation Package (VASP).
129
questions
3
votes
0answers
18 views
SCAN-RVV10 geometry optimization
I'm using SCAN-RVV10 to optimize hexagonal-BN but optimized geometry not looking true as the calculated interlayer distance is far smaller than the experimental value(exp=3.35, calc=3.20)(SCAN-RVV10 ...
5
votes
0answers
21 views
What are the input parameters of VASP for 2D material geometry optimization?
Apparently, my input parameters are not good for geometry relaxation of 2D materials using VASP.
...
5
votes
1answer
68 views
VASP error when trying to do calculations in the presence of an electric field
I am trying to observe the effect of the electric field on 2D materials. I applied electric field by introducing three tags:
...
7
votes
1answer
141 views
Number of KPOINTS in irreducible part of Brillouin zone
I want to investigate the comparison of Total Energy per cell with respect to the number of KPOINTS in irreducible part of Brillouin zone but I do not know how to calculate the number of KPOINTS with ...
6
votes
2answers
174 views
How to perform band-structure unfolding in VASP?
I have created a band structure for 3x3x1 doped-supercell using VASP, and I obtained the figure below. Now I want to do band-unfolding. What are the simplest ways ...
8
votes
1answer
96 views
Single point energy calculation in VASP
I want to do single point energy calculations in VASP for $\ce{Mg2Si}$ so what should be initial steps to do? What are tags required in INCAR sufficient to do this ...
7
votes
1answer
71 views
Molecular Dynamics Simulations in VASP
I want to run molecular dynamics (MD) simulations with VASP for Mg2Si to investigate the simulation time vs ENCUT and KPOINTS, ...
6
votes
0answers
55 views
Phonon Frequencies and Free Energy with respect to polymorphs
I have a material that can crystallize in either a cubic or tetragonal polymorph depending on the synthesis. I used DFPT in VASP and calculated the phonon band structures. I see that the cubic has all ...
9
votes
1answer
102 views
How to calculate the formation energy of a monolayer using VASP?
I want to calculate the formation energy of WS2 monolayer unit cell using VASP. I am wandering if you could show me the detailed ...
5
votes
0answers
46 views
In VASP, which option is better for monolayer relaxation: ISIF=3 or ISIF=4?
Since I have started working on monolayers I was using the ISIF=3 tag for relaxation, this was after recompiling VASP with the modified "...
5
votes
2answers
80 views
Bash script to extract lattice parameters from CONTCAR
I am using VASP to calculate material properties. I want to know how to extract the lattice parameters from my cells automatically with a script. I know about the method with VESTA (described here How ...
5
votes
1answer
73 views
How to do VASP convergence tests, and how to get two plots of Encut and k-points wrt to total energy? I want to do convergence for Mg2Si
I am using VASP for the first time and do not know how to do convergence tests. How are convergence tests done in VASP and how do we get two plots of Encut and k-points with respect to total energy? I ...
8
votes
1answer
81 views
What is the source of error in this mBJ-LDA calculation?
I am trying to do MBJLDA calculation for bandstructure for WS2 monolayer unit cell using VASP and following the method provided here : Band Structure mBJ-LDA using Vasp, but I am getting an error ...
7
votes
1answer
105 views
How to study a new material without any experimental data about it?
My question is a little bit general. I want to study a 2D monolayer material which hasn't any experimental data available, just some first principles DFT works using PBE, LDA and HSE06 (for band ...
6
votes
1answer
73 views
How can I find the exciton-binding energy (optical gap) with VASP?
What is the best way to find the exciton-binding energy using VASP?
I have heard about the method of calculating it through the dielectic tensor with local field effects and effective masses, but I'm ...
6
votes
1answer
61 views
How to carry out HSE06+SOC band structure calculation using VASP?
I could not find any good source for this type of calculation. I'd be very appreciated if someone who is experienced with that to show it step by step
5
votes
1answer
78 views
How to calculate the enthalpy of formation?
I am following this paper to calculate the formation enthalpy of MgCu$_2$, in which the formation enthalpy is defined as follows:
where $E$(Mg$_x$X$_y$) is the total energy of the compound, and $E$(...
5
votes
1answer
34 views
Are these settings for HSEsol accurate enough?
I have conducted HSEsol relaxation on a monolayer unit cell of 3 atoms using VASP, with the settings below :
...
7
votes
1answer
76 views
Will there be a difference between GGA and GGA+$U$ for material with Sc element involved?
I have a material that contains the transition metal element Sc [3$d$1], and I want to know your opinions if there will be a difference between GGA and GGA+$U$ calculation. Knowing that the other ...
9
votes
1answer
89 views
How to perform HSEsol in VASP calculations?
I want to perform HSEsol (PBEsol + HSE06) calculation on a material (monolayer) that doesn't have experimental data available. Could you please tell me how to ...
7
votes
3answers
238 views
How to determine the value of the difference (U-J) in “Dudarev's approach” for GGA+U calculation using the VASP?
I want to conduct GGA+U calculations using Duradev's approach in VASP code on a ...
5
votes
1answer
34 views
Fermi level shift downward in the thin film structure
I did a band structure calculation of a thin film structure with different number of atomic layers. I found that the original bulk gap was shifted upward and the Fermi level was shifted downward no ...
12
votes
1answer
108 views
Structure relaxation of a thin film structure in VASP
I have some general questions about doing the structure relaxation of a thin film structure in VASP. I want to study the how the band structure evolves as we increase the number of layers of the ...
7
votes
2answers
175 views
What is the meaning of the “PRIMCELL.vasp” file generated by VASPKIT tool during bandstructure inputs generation?
When I use VASPKIT tool to generate K-path KPOINTS file for Bandstructure calcualtion of a 4x4x1 supercell of a pure material, ...
10
votes
2answers
101 views
How to create a KPOINTS file (k-path) for 4x4x1 supercell bandstructure calculation?
How to generate or create the correct KPOINTS ( K-PATH) file for a 4x4x1 supercell bandstructure calculation ? Is there a software compatible with vasp can do that ?...
10
votes
1answer
64 views
Why does the VASP electronic step not stop after getting converged?
I have just implemented VASP code with Gamma K-point, POSCAR of 128-atom supercell and INCAR like this:
...
11
votes
1answer
210 views
Are different eigensolvers consistent within VASP (Algo=Normal vs Fast)
I tried to relax a 4x4x1 supercell of ferromagnetic monolayer material using the default settings (ALGO = Normal) but it didn't converge. So, I switched to ...
8
votes
2answers
126 views
inconsistent behavior between band structure and density of states
I'm a beginner in DFT calculation. I have performed a DFT calculation on CuCoSnSe using PBE-GGA on Quantum Esspresso. When I plot the band structure and the total DOS, the band structure shows a ...
12
votes
1answer
134 views
Band structure and density of states disagreement (mp-19092)
My question is both specific and general. While looking through the materials project database I found this entry. The band structure reported and density of states are dramatically different it ...
9
votes
1answer
46 views
Does the DOS plotted by p4vasp already have Fermi energy subtracted?
I have used both SUMO and P4VASP to generate a DOS plot. I have found that there's a shift (displacement) between the two DOS ...
11
votes
1answer
74 views
DFT optical calculation and plotting for real and imaginary permittivity in VASP?
I have calculated Frequency dependent optical permittivity of Au using (VASP) my INCAR tag includes LOPTICS=.TURE., my OUTCAR ...
7
votes
0answers
44 views
Charge density convergence within VASP using spin polarized DFT+U
I am noticing a possible convergence problem in a magnetic U system I am studying. In the OSZICAR file I often see the rms(c) value go to about 0.2e+3 and stabilize. Can anyone suggest what may be ...
7
votes
1answer
59 views
ISMEAR and SIGMA
I'm calculating the total energy at the ACFDT-RPA level using VASP in terms of this tutorial. For the first three steps it uses:
ISMEAR = 0 ; SIGMA = 0.05
but for ...
7
votes
0answers
74 views
The gap was open when I was doing an HSE + SOC DFT calculation
I used VASP as my DFT software to do a calculation on an anti-perovskite crystal. I try to reproduce the band structure from literature which was calculated based on HSE + SOC calculation. Their ...
8
votes
1answer
152 views
Why do we need to build a supercell to use the DFPT in Phonopy interfaced with VASP?
The following passage about the merits of density-functional perturbation theory (DFPT) is extracted from this seminal paper: Phonons and related crystal properties from density-functional ...
2
votes
1answer
75 views
BSE and IQP oscillator strength from VASP
Recently I am trying to calculate the BSE and IQP transition dipole based on VASP lecture on BSE and BSE fatband. However, I have a few questions regarding the BSE and IQP oscillator strength. From ...
10
votes
1answer
104 views
How many GB of RAM would be needed for VASP to evaluate optical properties of a material?
Even though it is a powerful tool, Quantum ESPRESSO's hardware requirements are very high. For instance, to evaluate optical properties, even for structures with tens of atoms, Quantum ESPRESSO can ...
8
votes
1answer
164 views
What are the pitfalls for the simulation of MOF materials with VASP?
I want to study the properties of metal-organic framework (MOF) materials with DFT implemented in VASP. What's the pitfall for this kind of simulation? Which points should I take special care of?
I ...
14
votes
1answer
182 views
How can you separate the data plot for spin up and spin down band structure into 2 different graphs, in Pymatgen?
I am a beginner user of Pymatgen package. In order to process the data from VASP DFT calculation software, I use Pymatgen to visualise the output band structure. When I do spin polarised band ...
12
votes
2answers
369 views
How to start with the optical properties of 2D materials with the VASP code?
I hope you are doing well. I am new to VASP code, my project is "Optical properties of 2D materials on VASP" but I have no idea how to run a simple calculation on VASP. I will be very ...
8
votes
1answer
72 views
How to remove HSE06 bandstructure fake k-points from vasprun.xml file?
Is there any script that can remove fake k-points from a vasprun.xmlfile for HSE06 bandstructure calculation? because removing it manually is a time consuming task.
6
votes
0answers
67 views
How to build amorphous Al2O3 using the AIMD method implemented in VASP?
I want to build amorphous Al$_2$O$_3$ with the AIMD (ab-initio molecular dynamics) method implemented in VASP.
I know that two procedures should be taken into account, namely
1st: melt
2nd: quench
...
6
votes
1answer
56 views
How better is PAW available in VASP when compared to that present in PS Library?
Papers with DFT calculations that use VASP work with PAW pseudopotentials which are also available in PS Library. I assume they are different since VASP is commercial. Given that, how different are ...
14
votes
4answers
851 views
How can I visualize the trajectory of a VASP simulation?
Which software package(s) can be used to visualize the trajectory of VASP MD simulation?
VMD claims that there is a plugin to read the VASP output, while in the last version for Linux, I did not find ...
6
votes
1answer
129 views
Find the value of density of states at the Fermi energy using VASP
VASP has a tag NEDOS, which helps specify the # of points on which the DoS is evaluated. Other than that, we have EMIN and EMAX, which help decide the range of ...
11
votes
4answers
247 views
Create doped structures to POSCAR files for vasp
I have a perfect supercell structure Ni fcc. And I would like to dope another element O or N with a ratio of O:Ni=8:100 to the supercell of 3x3x3 and find the most stable ordering structure. The ...
10
votes
0answers
72 views
Converge number of layers of atoms or number of unit cells for adsorption calculations? [closed]
I'm trying to calculate the adsorption energies of various adsorbates on Fe2O3 surfaces (although, with there being many possible surfaces for Fe2O3 it is quite complex, but that's for another time...)...
8
votes
1answer
88 views
Electron Affinity of Semiconductors via DFT
Can we calculate electron affinity of a semiconductor (e.g., for Si) using density functional theory calculations in VASP? Which calculations are needed to compute electron affinity and band offsets?
10
votes
1answer
75 views
Binding energy calculation for Zn atom on armchair graphene slab?
I am trying to repeat the result of this paper for Zn absorbed on the armchair graphene slab.
The relaxed top and side structures are the following:
The relaxed structure is almost the same as the ...
9
votes
1answer
172 views
How to set vacuum space for slabs?
Let's say I want to work with the slabs, and I want to add 20 Angstrom vacuum space. Do I need just to set lattice parameter c=20 and k-point 1 in this direction?
