Bandgap of Si using different DFT+HF methods

Description: Bandgap of Si using different DFT+HF schemes (PBE, B3LYP, PBE0, HSE06, and HF)

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• INCAR

## Better preconverge with PBE first!

## Selects the B3LYP hybrid function
#LHFCALC = .TRUE. ; GGA = B3 ; AEXX = 0.2 ; AGGAX = 0.72 
#AGGAC = 0.81 ; ALDAC = 0.19
#ALGO = D ; TIME = 0.4 

## Selects the PBE0  hybrid function
#LHFCALC = .TRUE. ; 
#ALGO = D ; TIME = 0.4 

## Selects the HSE06 hybrid function
#LHFCALC = .TRUE. ; HFSCREEN = 0.2 ; 
#ALGO = D ; TIME = 0.4 

## Selects HF 
#LHFCALC = .TRUE. ; AEXX = 1.0 ; ALDAC = 0.0 ; AGGAC = 0
#ALGO = D ; TIME = 0.4 

## Leave this in
ISMEAR =  0
SIGMA  =  0.01
GGA    = PE

• KPOINTS

k-points
0
Gamma
  4  4  4
  0  0  0

• POSCAR

System: Si                             
 5.430 
 0.5 0.5 0.0
 0.0 0.5 0.5
 0.5 0.0 0.5
   1  
Cartesian
0    0    0
0.25 0.25 0.25

• script to extract eigenvalues and calculate the bandgap

grep "      4     " OUTCAR | head -8 | \
awk 'BEGIN{i=1}{a[i]=$2 ; i=i+1} END{for (j=1;j<i;j++) print j,a[j]}' > vband.dat
grep "      5     " OUTCAR | head -8 | \
awk 'BEGIN{i=1}{a[i]=$2 ; i=i+1} END{for (j=1;j<i;j++) print j,a[j]}' > cband.dat

Download

5.1_Si_Hybrids.tgz

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