Band structure calculation
Posted: Fri Aug 24, 2012 1:53 pm
Hi
I want to calculate the band structure for 2 systems : a small one (4 atoms) and a large one (399) atoms.
I already made a first calculation for both systems to converge.
For the small system, I used this KPOINTS file :
Automatic
0
GMonk-P
21 21 1
0 0 0
2D system so I need only 1 K point in z direction
For the large system, is used fewer K points :
Automatic
1
Reciproque
0.666666 0.333333 0. 1.
Now I want to calculate the band struture
1) small system
I can get a band structure out of this with : ICHARG = 11
My question : do I need a finer k-mesh grid before calculating the band struture ? I mean doing a static selfconsistent run with more K points (like 42 42 1).
2) large system
To get a more accurate band structure (and DOS) I think I MUST do a static selfconsistent run with more KPOINTS.
question : Am I doing OK with this configuration ?
in INCAR :
ISTART = 1 : restart from previous charge density
NSW = 0 : no ionic loop, just an electronic loop
IBRION = -1 : no ionic update (ions are kept fixed)
in KPOINTS :
Automatic
0
GMonk-P
3 3 1
0 0 0
And only after that, I can calculate the band struture.
Thanks
JF
I want to calculate the band structure for 2 systems : a small one (4 atoms) and a large one (399) atoms.
I already made a first calculation for both systems to converge.
For the small system, I used this KPOINTS file :
Automatic
0
GMonk-P
21 21 1
0 0 0
2D system so I need only 1 K point in z direction
For the large system, is used fewer K points :
Automatic
1
Reciproque
0.666666 0.333333 0. 1.
Now I want to calculate the band struture
1) small system
I can get a band structure out of this with : ICHARG = 11
My question : do I need a finer k-mesh grid before calculating the band struture ? I mean doing a static selfconsistent run with more K points (like 42 42 1).
2) large system
To get a more accurate band structure (and DOS) I think I MUST do a static selfconsistent run with more KPOINTS.
question : Am I doing OK with this configuration ?
in INCAR :
ISTART = 1 : restart from previous charge density
NSW = 0 : no ionic loop, just an electronic loop
IBRION = -1 : no ionic update (ions are kept fixed)
in KPOINTS :
Automatic
0
GMonk-P
3 3 1
0 0 0
And only after that, I can calculate the band struture.
Thanks
JF