Cd Si volume relaxation: Difference between revisions
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{{TAGBL|ISMEAR}} = 0; {{TAGBL|SIGMA}} = 0.1; | {{TAGBL|ISMEAR}} = 0; {{TAGBL|SIGMA}} = 0.1; | ||
{{TAGBL|ENMAX}} = 240 | {{TAGBL|ENMAX}} = 240 | ||
{{TAGBL|IBRION}}=2; {{TAGBL|ISIF}}=3 ; {{TAGBL|NSW}}=15 | {{TAGBL|IBRION}} = 2; {{TAGBL|ISIF}}=3 ; {{TAGBL|NSW}}=15 | ||
{{TAGBL|EDIFF}} = 0.1E-04 | {{TAGBL|EDIFF}} = 0.1E-04 | ||
{{TAGBL|EDIFFG}} = -0.01 | {{TAGBL|EDIFFG}} = -0.01 | ||
*{{TAG|IBRION}}=2 conjugate-gradient algorithm. | |||
*{{TAG|ISIF}}=3 change of internal parameter, shape and volume simultaneously. | |||
=== {{TAG|KPOINTS}} === | === {{TAG|KPOINTS}} === | ||
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== Calculation == | == Calculation == | ||
*To determine the equilibrium volume we can: | |||
**Fit the energz over a certain volume range to an equation of state (see {{TAG|cd_Si}}. | |||
**Alternatively we relax the structure with VASP "on the fly" ({{TAG|IBRION}}=2 and {{TAG|ISIF}}=3) | |||
*From equation of states we determine lattice parameter of <math>a=5.4687 !, \AA</math> (volume scan plus Murnaghan EOS using {{TAG|ENMAX}}=400). | |||
Revision as of 18:56, 8 May 2017
Overview > fcc Si > fcc Si DOS > fcc Si bandstructure > cd Si > cd Si volume relaxation > cd Si relaxation > beta-tin Si > fcc Ni > graphite TS binding energy > graphite MBD binding energy > graphite interlayer distance > List of tutorials
Task
Relaxation of the internal coordinates, volume and cell shape in cd Si.
Input
POSCAR
cubic diamond 5.5 0.0 0.5 0.5 0.5 0.0 0.5 0.5 0.5 0.0 2 Direct -0.125 -0.125 -0.125 0.125 0.125 0.125
INCAR
System = diamond Si ISMEAR = 0; SIGMA = 0.1; ENMAX = 240 IBRION = 2; ISIF=3 ; NSW=15 EDIFF = 0.1E-04 EDIFFG = -0.01
- IBRION=2 conjugate-gradient algorithm.
- ISIF=3 change of internal parameter, shape and volume simultaneously.
KPOINTS
k-points 0 Monkhorst Pack 11 11 11 0 0 0
Calculation
- To determine the equilibrium volume we can:
- From equation of states we determine lattice parameter of (volume scan plus Murnaghan EOS using ENMAX=400).
Download
To the list of examples or to the main page