MgO optimum mixing: Difference between revisions
No edit summary |
No edit summary |
||
Line 3: | Line 3: | ||
---- | ---- | ||
*{{TAG|INCAR}} | *{{TAG|INCAR}} | ||
############################################## | |||
############################################## | ## Optimum HSE mixing parameter ({{TAGBL|AEXX}}) for MgO | ||
## Optimum HSE mixing parameter (AEXX) for MgO | ## Expt gap = 7.8 eV | ||
## Expt gap = 7.8 eV | ## fit gap wrt. 0<{{TAGBL|AEXX}}<1 | ||
## fit gap wrt. 0<AEXX<1 | ## Compute the bandgap using different value of {{TAGBL|AEXX}} | ||
## Compute the bandgap using different value of AEXX | ## in the range (0,1) and find the value which leads | ||
## in the range (0,1) and find the value which leads | ## to the best agreement with the experimental gap. | ||
## to the best agreement with the experimental gap. | ## hint: the gap grows lineraly with {{TAGBL|AEXX}} | ||
## hint: the gap grows lineraly with AEXX | ## Better preconverge with PBE first! | ||
## Better preconverge with PBE first! | ############################################## | ||
############################################## | |||
## Selects the HSE06 hybrid function | |||
## Selects the HSE06 hybrid function | #{{TAGBL|LHFCALC}} = .TRUE. ; {{TAGBL|HFSCREEN}} = 0.2 ; {{TAGBL|AEXX}}=0.25 | ||
#LHFCALC = .TRUE. ; HFSCREEN = 0.2 ; AEXX=0.25 | #{{TAGBL|ALGO}} = D ; {{TAGBL|TIME}} = 0.4 | ||
#ALGO = D ; TIME = 0.4 | |||
## Leave this in | |||
## Leave this in | {{TAGBL|ISMEAR}} = 0 | ||
ISMEAR = 0 | {{TAGBL|SIGMA}} = 0.01 | ||
SIGMA = 0.01 | {{TAGBL|GGA}} = PE | ||
GGA = PE | |||
*{{TAG|KPOINTS}} | *{{TAG|KPOINTS}} | ||
Line 58: | Line 55: | ||
The bandgap is obainted by substracting the eigenvalues written in cband.dat (conduction band | The bandgap is obainted by substracting the eigenvalues written in cband.dat (conduction band | ||
minimum at Gamma) and vband.dat (valence band maximum at Gamma) | minimum at Gamma) and vband.dat (valence band maximum at Gamma) | ||
== Download == | == Download == |
Revision as of 10:55, 15 March 2017
Description: find optimum HSE mixing parameter for MgO
############################################## ## Optimum HSE mixing parameter (AEXX) for MgO ## Expt gap = 7.8 eV ## fit gap wrt. 0<AEXX<1 ## Compute the bandgap using different value of AEXX ## in the range (0,1) and find the value which leads ## to the best agreement with the experimental gap. ## hint: the gap grows lineraly with AEXX ## Better preconverge with PBE first! ############################################## ## Selects the HSE06 hybrid function #LHFCALC = .TRUE. ; HFSCREEN = 0.2 ; AEXX=0.25 #ALGO = D ; TIME = 0.4 ## Leave this in ISMEAR = 0 SIGMA = 0.01 GGA = PE
k-points 0 Gamma 4 4 4 0 0 0
MgO -18.79350000000000000000 0.5 0.5 0.0 0.0 0.5 0.5 0.5 0.0 0.5 1 1 cart 0.00 0.00 0.00 0.50 0.0 0.0
- script to extract G-eigenvalues and calculate the bandgap
grep " 4 " OUTCAR | head -8 | \ awk 'BEGIN{i=1}{a[i]=$2 ; i=2} 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=2} END{for (j=1;j<i;j++) print j,a[j]}' > cband.dat
The bandgap is obainted by substracting the eigenvalues written in cband.dat (conduction band minimum at Gamma) and vband.dat (valence band maximum at Gamma)
Download
To the list of examples or to the main page