Fcc Ni: Difference between revisions

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== Task ==
== Task ==


Lattice constant optimization in (spin-polarized) fcc Ni.
Lattice parameter optimization, calculation of the DOS and bandstructure in (spin-polarized) fcc Ni.


== Input ==
== Input ==
Line 22: Line 22:
   {{TAGBL|ENCUT}}  =    270
   {{TAGBL|ENCUT}}  =    270
   {{TAGBL|ISMEAR}} =    1  ; {{TAGBL|SIGMA}} = 0.2
   {{TAGBL|ISMEAR}} =    1  ; {{TAGBL|SIGMA}} = 0.2
   {{TAGBL|LORBIT}}=11
   {{TAGBL|LORBIT}} = 11
     
   {{TAGBL|ISPIN}} = 2
   {{TAGBL|ISPIN}}=2
   {{TAGBL|MAGMOM}} = 1
   {{TAGBL|MAGMOM}} = 1
*Initial charge-density from overlapping atoms in starting job.
*Default energy cutoff of 270 eV used ({{TAG|ENCUT}}=270).
*MP smearing used since we have a metal.
*Spin-polarized calculation {{TAG|ISPIN}}=2, initial moments of 1 ({{TAG|MAMOM}}=1.
*Static calculation.


=== {{TAG|KPOINTS}} ===
=== {{TAG|KPOINTS}} ===
Line 33: Line 38:
   11 11 11
   11 11 11
   0  0  0
   0  0  0
*Equally spaced k mesh with 56 points in the IBZ.
*Odd, <math>\Gamm</math>-centered mesh.


== Calculation ==
== Calculation ==


*


*The bash-script <tt>loop.sh</tt> runs fcc Ni at several different lattice constants (3.0-3.9 Å) and collects free energy versus lattice constant into the file SUMMARY.fcc:
*The bash-script <tt>loop.sh</tt> runs fcc Ni at several different lattice constants (3.0-3.9 Å) and collects free energy versus lattice constant into the file SUMMARY.fcc:

Revision as of 11:59, 10 May 2017

Task

Lattice parameter optimization, calculation of the DOS and bandstructure in (spin-polarized) fcc Ni.

Input

POSCAR

fcc:
 3.53 
 0.5 0.5 0.0
 0.0 0.5 0.5
 0.5 0.0 0.5
   1
cartesian
0 0 0

INCAR

  SYSTEM = fcc Ni
  ISTART = 0 ; ICHARG=2
  ENCUT  =    270
  ISMEAR =    1  ; SIGMA = 0.2
  LORBIT = 11
  ISPIN = 2
  MAGMOM = 1
  • Initial charge-density from overlapping atoms in starting job.
  • Default energy cutoff of 270 eV used (ENCUT=270).
  • MP smearing used since we have a metal.
  • Spin-polarized calculation ISPIN=2, initial moments of 1 (MAMOM=1.
  • Static calculation.

KPOINTS

k-points
 0
Monkhorst Pack
 11 11 11
 0  0  0
  • Equally spaced k mesh with 56 points in the IBZ.
  • Odd, Failed to parse (Conversion error. Server ("cli") reported: "[INVALID]"): {\displaystyle \Gamm} -centered mesh.

Calculation

  • The bash-script loop.sh runs fcc Ni at several different lattice constants (3.0-3.9 Å) and collects free energy versus lattice constant into the file SUMMARY.fcc:
#! /bin/bash
BIN=/path/to/your/vasp/executable
rm WAVECAR SUMMARY.fcc
for i in 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 ; do
cat >POSCAR <<!
fcc:
   $i
 0.5 0.5 0.0
 0.0 0.5 0.5
 0.5 0.0 0.5
   1
cartesian
0 0 0
!
echo "a= $i" ; mpirun -n 2 $BIN
E=`awk '/F=/ {print $0}' OSZICAR` ; echo $i $E  >>SUMMARY.fcc
done
cat SUMMARY.fcc
  • With the bash-scripts dos.sh and band.sh compute the DOS and bandstructure of fcc Ni, respectively.

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).

  • To make a quick plot of SUMMARY.fcc try:
gnuplot
gnuplot> plot "SUMMARY.fcc" using ($1):($4) w lp

Download

fccNi.tgz


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