Si bandstructure

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Revision as of 15:11, 8 June 2012 by Cesare (talk | contribs)

Description: Bandstructure for Si within DFT+HF

Mind: For PBE bandstructure refer to Fcc Si bandstructure example.


  • INCAR
## Do a HSE hybrid functional banstructure
## calculation with (i) the KPOINTS.HSE.G-X file
## and (2) using VASP2WANNIER90
## Better first preconverge with DFT and then
## restart with the settings below!

## Default       
ISMEAR =  0
SIGMA  =  0.01
GGA    = PE

## HSE
#LHFCALC = .TRUE. ; HFSCREEN = 0.2 ; AEXX = 0.25
#ALGO = D ; TIME = 0.4 ; LDIAG = .TRUE.

##VASP2WANNIER
#LWANNIER90=.TRUE.
  • KPOINTS
Automatically generated mesh
 0
G
 4 4 4
 0 0 0
  • KPOINTS_HSE_bands
Explicit k-points list
      18
Reciprocal lattice
    0.00000000000000    0.00000000000000    0.00000000000000             1
    0.25000000000000    0.00000000000000    0.00000000000000             8
    0.50000000000000    0.00000000000000    0.00000000000000             4
    0.25000000000000    0.25000000000000    0.00000000000000             6
    0.50000000000000    0.25000000000000    0.00000000000000            24
   -0.25000000000000    0.25000000000000    0.00000000000000            12
    0.50000000000000    0.50000000000000    0.00000000000000             3
   -0.25000000000000    0.50000000000000    0.25000000000000             6
0.00000000 0.00000000 0.00000000 0.000
0.00000000 0.05555556 0.05555556 0.000
0.00000000 0.11111111 0.11111111 0.000
0.00000000 0.16666667 0.16666667 0.000
0.00000000 0.22222222 0.22222222 0.000
0.00000000 0.27777778 0.27777778 0.000
0.00000000 0.33333333 0.33333333 0.000
0.00000000 0.38888889 0.38888889 0.000
0.00000000 0.44444444 0.44444444 0.000
0.00000000 0.50000000 0.50000000 0.000

  • POSCAR
system Si
5.430
0.5 0.5 0.0
0.0 0.5 0.5
0.5 0.0 0.5
2
cart
0.00 0.00 0.00
0.25 0.25 0.25
  • wannier90.win
num_wann=8
num_bands=8

Begin Projections
Si:sp3
End Projections

dis_froz_max=9
dis_num_iter=1000

guiding_centres=true

#restart         =  plot
#bands_plot      =  true
#begin kpoint_path
#L 0.50000  0.50000 0.5000 G 0.00000  0.00000 0.0000
#G 0.00000  0.00000 0.0000 X 0.50000  0.00000 0.5000
#X 0.50000  0.00000 0.5000 K 0.37500 -0.37500 0.0000
#K 0.37500 -0.37500 0.0000 G 0.00000  0.00000 0.0000
#end kpoint_path
#bands_num_points 40
#bands_plot_format gnuplot xmgrace

begin unit_cell_cart
     2.7150000     2.7150000     0.0000000
     0.0000000     2.7150000     2.7150000
     2.7150000     0.0000000     2.7150000
end unit_cell_cart

begin atoms_cart
Si       0.0000000     0.0000000     0.0000000
Si       1.3575000     1.3575000     1.3575000
end atoms_cart

mp_grid =     4     4     4

begin kpoints
     0.0000000     0.0000000     0.0000000
     0.2500000     0.0000000     0.0000000
     0.5000000     0.0000000     0.0000000
     0.2500000     0.2500000     0.0000000
     0.5000000     0.2500000     0.0000000
    -0.2500000     0.2500000     0.0000000
     0.5000000     0.5000000     0.0000000
    -0.2500000     0.5000000     0.2500000
     0.0000000     0.2500000     0.0000000
     0.0000000     0.0000000     0.2500000
    -0.2500000    -0.2500000    -0.2500000
    -0.2500000     0.0000000     0.0000000
     0.0000000    -0.2500000     0.0000000
     0.0000000     0.0000000    -0.2500000
     0.2500000     0.2500000     0.2500000
     0.0000000     0.5000000     0.0000000
     0.0000000     0.0000000     0.5000000
    -0.5000000    -0.5000000    -0.5000000
     0.0000000     0.2500000     0.2500000
     0.2500000     0.0000000     0.2500000
    -0.2500000    -0.2500000     0.0000000
    -0.2500000     0.0000000    -0.2500000
     0.0000000    -0.2500000    -0.2500000
     0.0000000     0.5000000     0.2500000
     0.2500000     0.0000000     0.5000000
    -0.2500000    -0.2500000     0.2500000
    -0.5000000    -0.2500000    -0.5000000
     0.2500000     0.5000000     0.0000000
     0.2500000    -0.2500000    -0.2500000
    -0.5000000    -0.5000000    -0.2500000
     0.0000000     0.2500000     0.5000000
    -0.2500000     0.2500000    -0.2500000
    -0.2500000    -0.5000000    -0.5000000
     0.5000000     0.0000000     0.2500000
    -0.5000000    -0.2500000     0.0000000
     0.0000000    -0.5000000    -0.2500000
    -0.2500000     0.0000000    -0.5000000
     0.2500000     0.2500000    -0.2500000
     0.5000000     0.2500000     0.5000000
    -0.2500000    -0.5000000     0.0000000
    -0.2500000     0.2500000     0.2500000
     0.5000000     0.5000000     0.2500000
     0.0000000    -0.2500000    -0.5000000
     0.2500000    -0.2500000     0.2500000
     0.2500000     0.5000000     0.5000000
    -0.5000000     0.0000000    -0.2500000
     0.0000000    -0.2500000     0.2500000
     0.2500000     0.0000000    -0.2500000
    -0.2500000    -0.2500000    -0.5000000
     0.2500000     0.5000000     0.2500000
     0.2500000    -0.2500000     0.0000000
    -0.5000000    -0.2500000    -0.2500000
     0.2500000     0.2500000     0.5000000
     0.0000000     0.2500000    -0.2500000
    -0.2500000    -0.5000000    -0.2500000
     0.5000000     0.2500000     0.2500000
    -0.2500000     0.0000000     0.2500000
     0.0000000     0.5000000     0.5000000
     0.5000000     0.0000000     0.5000000
     0.2500000    -0.2500000     0.5000000
     0.5000000     0.2500000    -0.2500000
    -0.5000000    -0.2500000    -0.7500000
     0.2500000    -0.5000000    -0.2500000
    -0.2500000     0.2500000    -0.5000000
end kpoints
  • README.txt
Bandstructure plot in VASP (Three different ways)

1) Standard way: PBE (Fcc Si bandstructure example).
   1.1  Standard self-consistent (SC) run
   1.2  non-SC calculation (ICHARG=11) using preconverged CHGCAR file and KPOINTS_PBE_bands

2) Fake SC procedure: PBE & HSE
   2.1 Standard self-consistent (SC) run
   2.2 Additional SC-run using KPOINTS_HSE_bands

----
The file KPOINTS_HSE_bands is constructed by copying the IBZKPT file from run 2.1 to the KPOINTS file:

IBZKPT
Automatically generated mesh
       8
Reciprocal lattice
    0.00000000000000    0.00000000000000    0.00000000000000             1
    0.25000000000000    0.00000000000000    0.00000000000000             8
    0.50000000000000    0.00000000000000    0.00000000000000             4
    0.25000000000000    0.25000000000000    0.00000000000000             6
    0.50000000000000    0.25000000000000    0.00000000000000            24
   -0.25000000000000    0.25000000000000    0.00000000000000            12
    0.50000000000000    0.50000000000000    0.00000000000000             3
   -0.25000000000000    0.50000000000000    0.25000000000000             6

Then add the desired additional k-points with zero weight and change the total number of k-points

Explicit k-points list
      18 <--- CHANGE TOTAL NUMBER OF K-POINTS !!
Reciprocal lattice
    0.00000000000000    0.00000000000000    0.00000000000000             1
    0.25000000000000    0.00000000000000    0.00000000000000             8
    0.50000000000000    0.00000000000000    0.00000000000000             4
    0.25000000000000    0.25000000000000    0.00000000000000             6
    0.50000000000000    0.25000000000000    0.00000000000000            24
   -0.25000000000000    0.25000000000000    0.00000000000000            12
    0.50000000000000    0.50000000000000    0.00000000000000             3
   -0.25000000000000    0.50000000000000    0.25000000000000             6
0.00000000 0.00000000 0.00000000 0.000 <--- ZERO WEIGHT !!
0.00000000 0.05555556 0.05555556 0.000
0.00000000 0.11111111 0.11111111 0.000
0.00000000 0.16666667 0.16666667 0.000
0.00000000 0.22222222 0.22222222 0.000
0.00000000 0.27777778 0.27777778 0.000
0.00000000 0.33333333 0.33333333 0.000
0.00000000 0.38888889 0.38888889 0.000
0.00000000 0.44444444 0.44444444 0.000
0.00000000 0.50000000 0.50000000 0.000
----

3) VASP2WANNIER90: PBE, HSE & GW 
   3.1 Standard SC run using the existing wannier.win file  
   3.2 run wannier90 (wannier90.x wannier90) to generate MLWFs
   3.3 uncomment bandstructure plot flags in wannier90.win and restart wannier90

----
If the wannier90.win file does not exists VASP will create a default wannier90.win compatible with
the POSCAR and INCAR which need to be suitably modifiy by including the instruction required to generate 
the MLWFs (refer to the wannier90 manual):

default wannier90.win
 num_wann =     8  ! set to NBANDS by VASP

use_bloch_phases = .T.

begin unit_cell_cart
     2.7150000     2.7150000     0.0000000
     0.0000000     2.7150000     2.7150000
     2.7150000     0.0000000     2.7150000
end unit_cell_cart

begin atoms_cart
Si       0.0000000     0.0000000     0.0000000
Si       1.3575000     1.3575000     1.3575000
end atoms_cart

mp_grid =     4     4     4

begin kpoints
     0.0000000     0.0000000     0.0000000
     0.2500000     0.0000000     0.0000000
     0.5000000     0.0000000     0.0000000
     0.2500000     0.2500000     0.0000000
     0.5000000     0.2500000     0.0000000
    -0.2500000     0.2500000     0.0000000
     0.5000000     0.5000000     0.0000000
    -0.2500000     0.5000000     0.2500000
     0.0000000     0.2500000     0.0000000
     0.0000000     0.0000000     0.2500000
    -0.2500000    -0.2500000    -0.2500000
    -0.2500000     0.0000000     0.0000000
     0.0000000    -0.2500000     0.0000000
     0.0000000     0.0000000    -0.2500000
     0.2500000     0.2500000     0.2500000
     0.0000000     0.5000000     0.0000000
     0.0000000     0.0000000     0.5000000
    -0.5000000    -0.5000000    -0.5000000
     0.0000000     0.2500000     0.2500000
     0.2500000     0.0000000     0.2500000
    -0.2500000    -0.2500000     0.0000000
    -0.2500000     0.0000000    -0.2500000
     0.0000000    -0.2500000    -0.2500000
     0.0000000     0.5000000     0.2500000
     0.2500000     0.0000000     0.5000000
    -0.2500000    -0.2500000     0.2500000
    -0.5000000    -0.2500000    -0.5000000
     0.2500000     0.5000000     0.0000000
     0.2500000    -0.2500000    -0.2500000
    -0.5000000    -0.5000000    -0.2500000
     0.0000000     0.2500000     0.5000000
    -0.2500000     0.2500000    -0.2500000
    -0.2500000    -0.5000000    -0.5000000
     0.5000000     0.0000000     0.2500000
    -0.5000000    -0.2500000     0.0000000
     0.0000000    -0.5000000    -0.2500000
    -0.2500000     0.0000000    -0.5000000
     0.2500000     0.2500000    -0.2500000
     0.5000000     0.2500000     0.5000000
    -0.2500000    -0.5000000     0.0000000
    -0.2500000     0.2500000     0.2500000
     0.5000000     0.5000000     0.2500000
     0.0000000    -0.2500000    -0.5000000
     0.2500000    -0.2500000     0.2500000
     0.2500000     0.5000000     0.5000000
    -0.5000000     0.0000000    -0.2500000
     0.0000000    -0.2500000     0.2500000
     0.2500000     0.0000000    -0.2500000
    -0.2500000    -0.2500000    -0.5000000
     0.2500000     0.5000000     0.2500000
     0.2500000    -0.2500000     0.0000000
    -0.5000000    -0.2500000    -0.2500000
     0.2500000     0.2500000     0.5000000
     0.0000000     0.2500000    -0.2500000
    -0.2500000    -0.5000000    -0.2500000
     0.5000000     0.2500000     0.2500000
    -0.2500000     0.0000000     0.2500000
     0.0000000     0.5000000     0.5000000
     0.5000000     0.0000000     0.5000000
     0.2500000    -0.2500000     0.5000000
     0.5000000     0.2500000    -0.2500000
    -0.5000000    -0.2500000    -0.7500000
     0.2500000    -0.5000000    -0.2500000
    -0.2500000     0.2500000    -0.5000000
end kpoints
----

Wannier90 Manual @ [www.wannier.org/]

Download

5_4_Si_bandstructure.tgz


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