初めに
VASPの簡単な使い方を英語でまとめたものになります。
もうほとんど使うことはないと思うのでここに供養しておきます。
（2020年3月26日）
How to Use VASP
Structural optimization
Input files
POSCAR
Si
1.0
3.000000 3.000000 0.000000
0.000000 3.000000 3.000000
3.000000 0.000000 3.000000
Si
2
direct
0.000000 0.000000 0.000000
0.250000 0.250000 0.250000
| Line | Explanation |
|---|---|
| 1 | job name (arbitrary) |
| 2 | Fixed (recommended) |
| 3-5 | Primitive translation vectors |
| 6 | Atomic species |
| 7 | Number of atoms for each element |
| 8 | Fixed (recommended) |
| 9-10 | Atom positions for each atom (Cartesian coordinates representation) |
You can see the structure by a visualization software, VESTA.
KPOINTS
Auto
0
Gamma
5 5 5
0 0 0
| Line | Explanation |
|---|---|
| 1 | |
| 2 | |
| 3 | |
| 4 | |
| 5 |
INCAR
IBRION = 2
NSW = 300
ISIF = 3
ENCUT = 400
| Line | Explanation |
|---|---|
| 1 | Structual optimization IBRION = -1 : No optimization IBRION = 2 : Structural optimization with CG method |
| 2 | Maximum number of structural opt. |
| 3 | Option for structural optimization (Default is 2) |
| 4 | cutoff energy [eV] |
Option for structural optimization (ISIF)
| ISIF | calculate force | calculate stress tensor | relax ions | change cell shape | change cell volume |
|---|---|---|---|---|---|
| 0 | yes | no | yes | no | no |
| 1 | yes | trace only | yes | no | no |
| 2 | yes | yes | yes | no | no |
| 3 | yes | yes | yes | yes | yes |
| 4 | yes | yes | yes | yes | no |
| 5 | yes | yes | no | yes | no |
| 6 | yes | yes | no | yes | yes |
| 7 | yes | yes | no | no | yes |
POTCAR
cat ~~~/VASP/PP/Si/POTCAR > POTCAR
Output files
OUTCAR
You can see the total energy in the unit of eV.
FREE ENERGIE OF THE ION-ELECTRON SYSTEM (eV)
---------------------------------------------------
free energy TOTEN = -10.787124 eV
energy without entropy= -10.787690 energy(sigma->0) = -10.787313
CONTCAR
You can see the structure by a visualization software, VESTA.
Band structure calculation
Run SCF calculation
POSCAR
INCAR
KPOINTS
Auto
0
Gamma
5 5 5
0 0 0
KPOINTS generation for band structure calculations
syml
6
40 20 30 30 40
G 0.000 0.000 0.000
X 0.500 0.000 0.500
W 0.500 0.250 0.750
K 0.375 0.375 0.375
G 0.000 0.000 0.000
L 0.500 0.500 0.500
2.735494611 2.735494611 0.000000000 0.182782301 0.182782301 -0.182782301
0.000000000 2.735494611 2.735494611 -0.182782301 0.182782301 0.182782301
2.735494611 0.000000000 2.735494611 0.182782301 -0.182782301 0.182782301
-10.0 5.0
5.7993
| Line | Explanation |
|---|---|
| 1 | Total number of high symmetric k-points |
| 2 | Number of grid points between symmetric k-points |
| 3-8 | Symmetric k-points |
| 9-11 | Direct & reciprocal vector Copy and paste from OUTCAR |
| 12 | Energy range |
| 13 | Fermi energy Copy and paste from OUTCAR |
Terminal
> gfortran kpt-gen-vasp.f90
> ./a.out
> less KPOINTS
DFT calculation
INCAR
IBRION = -1
NSW = 0
EXCUT = 400
ICHARG = 11
| Line | Explanation |
|---|---|
| 4 | electron density is fixed |
Terminal
> gfortran eig2gp-vasp-largeband.f90
> ./a.out
> gnuplot band.gp