I would like to find the band structure and I have to give the Brillouin Zone path, But How? Please suggest me any video lectures or PDF for this content.
You can find a good tutorial in this web:
http://image.sciencenet.cn/olddata/kexue.com.cn/bbs/upload/20083418325986.pdf
... but I recommend Quantum Espresso (open source, a lot of documentation and a lot of help). http://www.quantum-espresso.org/
You can find a good tutorial at https://cms.mpi.univie.ac.at/marsweb/ . Specifically the second tutorial. However, the structure involved in this tutorial is fcc and diamond ones. If you know the space group of your system, you can find the Brillouin zone and k-vectors at the Bilbao crystallographic server: http://www.cryst.ehu.es/cryst/get_kvec.html. With these information all you need is to build the Brillouin path in the KPOINTS file and follow the tutorial I've mentioned above.
To generated ``strings'' of k-points connecting specific points of the Brillouin zone, the third line of the KPOINTS file must start with an ``L'' for line-mode:
k-points along high symmetry lines
10 ! 10 intersections
Line-mode
cart
0 0 0 ! gamma
0 0 1 ! X
0 0 1 ! X
0.5 0 1 ! W
0.5 0 1 ! W
0 0 1 ! gamma
VASP will generate 10 k-points, between the first and the second supplied point, 10 k-points between the third and the fourth, and another 10 points between the final two points. The coordinates of the k-points can be supplied in cartesian (4th line starts with c or k) or in reciprocal coordinates (4th line starts with r):
k-points along high symmetry lines
10 ! 10 intersections
Line-mode
rec
0 0 0 ! gamma
0.5 0.5 0 ! X
0.5 0.5 0 ! X
0.5 0.75 0.25 ! W
0.5 0.75 0.25 ! W
0 0 0 ! gamma
Defenetly use vasp tutorials and very important find the correct Brillouin zone and high symmetry k-point paths for your crystals using http://www.cryst.ehu.es/cryst/get_kvec.html
Dear Dr.Danylo Zherebetskyy ,
I want to ask my one query about high symmetric KPOINTS selection. You gave link in above post which we can use for bulk high symmetric KPOINTS generation but for surface bandgap calculation like 110. 001 etc how does choose high symmetric KPOINTS from above database or any other database.
Thank You
Shilendra
This is simple and short answer for new vasp users,
first using a particular functional you should optimize your KPOINT and ECUT
then for a band structure do a scf calculation using the optimized kpoint and cutoff ( Ecut).
for example you can use these keywords on your INCAR for scf :
PREC = Accurate
IBRION=-1
NSW=0
ENCUT=450 (what you optimized for your own material)
ISMEAR = 0 ; SIGMA = 0.10
then in second step you should run a non-scf calculation. in nscf calculation ,we must use '' ICHARG = 11'' to read charge file that you got in previous step .(''CHGCAR file'')
for Koint you should use primitive reciprocal lattice vectors and based on your material lattice , you can find it in this paper:
Article Setyawan, W. & Curtarolo, S. High-throughput electronic band...
this article gives you the path for plotting band structures.
for example i have a face centered cubic (fcc) lattice
for kpoint i must use this path :
G –X–W–K– G –L–U–W–L–K
which G(gamma) is (0,0,0)
X= (0.5,0,0.5) and ...
in the end you can use gnuplot or p4v and other scripts to plot the band structures.
wish all you the bests
Nima.
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