Cd Si: Difference between revisions
No edit summary |
No edit summary |
||
| Line 8: | Line 8: | ||
=== {{TAG|POSCAR}} === | === {{TAG|POSCAR}} === | ||
cubic diamond | cubic diamond | ||
5.5 | 5.5 | ||
| Line 36: | Line 37: | ||
== Calculation == | == Calculation == | ||
=== Volume relaxation === | |||
*The bash-script <tt>loop.sh</tt> runs Si in the cubic diamond (cd) structure at several different lattice constants (5.1-5.7 Å) and collects free energy versus lattice constant into the file SUMMARY.dia: | *The bash-script <tt>loop.sh</tt> runs Si in the cubic diamond (cd) structure at several different lattice constants (5.1-5.7 Å) and collects free energy versus lattice constant into the file SUMMARY.dia: | ||
| Line 77: | Line 80: | ||
*Extracted lattice parameter should be at 5.465 <math>\AA</math>. | *Extracted lattice parameter should be at 5.465 <math>\AA</math>. | ||
=== DOS === | |||
=== Bandstructure === | |||
'''Mind''': You will have to set the correct path to your VASP executable (i.e., <tt>BIN</tt>), and invoke VASP with the correct command (e.g., in the above: <tt>mpirun -np 2</tt>). | '''Mind''': You will have to set the correct path to your VASP executable (i.e., <tt>BIN</tt>), and invoke VASP with the correct command (e.g., in the above: <tt>mpirun -np 2</tt>). | ||
Revision as of 17:53, 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
Volume relaxtion of cubic diamond (cd) Si and the calculation of the DOS and bandstructure.
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
- Diamond Si starting lattice constant of 5.5 .
- Fcc cell.
- 2 atoms in cell.
INCAR
System = diamond Si ISTART = 0 ; ICHARG=2 ENCUT = 240 ISMEAR = 0; SIGMA = 0.1
KPOINTS
k-points 0 Monkhorst Pack 11 11 11 0 0 0
Calculation
Volume relaxation
- The bash-script loop.sh runs Si in the cubic diamond (cd) structure at several different lattice constants (5.1-5.7 Å) and collects free energy versus lattice constant into the file SUMMARY.dia:
#! /bin/bash
BIN=/path/to/your/vasp/executable
rm WAVECAR SUMMARY.dia
for i in 5.1 5.2 5.3 5.4 5.5 5.6 5.7 ; do
cat >POSCAR <<!
cubic diamond
$i
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
!
echo "a= $i" ; mpirun -n 2 $BIN
E=`awk '/F=/ {print $0}' OSZICAR` ; echo $i $E >>SUMMARY.dia
done
cat SUMMARY.dia
- Example output of SUMMARY.dia:
5.2 1 F= -.10528151E+02 E0= -.10528137E+02 d E =-.274709E-04 5.3 1 F= -.10713281E+02 E0= -.10713280E+02 d E =-.218410E-05 5.4 1 F= -.10806685E+02 E0= -.10806685E+02 d E =-.114401E-06 5.5 1 F= -.10823039E+02 E0= -.10823039E+02 d E =-.429842E-08 5.6 1 F= -.10775102E+02 E0= -.10775102E+02 d E =-.204668E-09 5.7 1 F= -.10673578E+02 E0= -.10673578E+02 d E =-.112715E-10 5.8 1 F= -.10528393E+02 E0= -.10528393E+02 d E =-.552513E-11
- To make a quick plot of SUMMARY.dia try:
gnuplot gnuplot> plot "SUMMARY.dia" using ($1):($4) w lp
- Extracted lattice parameter should be at 5.465 .
DOS
Bandstructure
Mind: You will have to set the correct path to your VASP executable (i.e., BIN), and invoke VASP with the correct command (e.g., in the above: mpirun -np 2).
Download
To the list of examples or to the main page