Ni 111 surface relaxation: Difference between revisions

From VASP Wiki
No edit summary
 
(16 intermediate revisions by the same user not shown)
Line 1: Line 1:
Description: relax the first two layers of a Ni (111) surface.
{{Sur_sci - Tutorial}}


----
== Task ==
*{{TAG|INCAR}}
Relaxation of the first two layers of a Ni (111) surface.
<pre>
general:
  ISTART = 0
  ICHARG = 2
  SYSTEM = clean (111) surface
  ENMAX  = 270
  ISMEAR =    2  ; SIGMA = 0.2
  ALGO= Fast
  EDIFF = 1E-6


dynamic:
== Input ==
  NSW=100
  POTIM = 0.8
  IBRION = 1
</pre>
 
*{{TAG|KPOINTS}}
<pre>
k-points
0
Monkhorst-Pack
9 9 1
0 0 0
</pre>


*{{TAG|POSCAR}}
=== {{TAG|POSCAR}} ===
<pre>
<pre>
  fcc (111) surface
  fcc (111) surface
Line 45: Line 23:
</pre>
</pre>


== Used INCAR Tags ==
*Similar setup as for {{TAG|Ni 100 surface relaxation}}.
*Again 2 of 5 layers relaxed.
*<math>(1-.444)\cdot 5.196 \cdot 3.53 \approx 10.2</math> <math>\AA</math> of vacuum.
 
=== {{TAG|INCAR}} ===
general:
  {{TAGBL|ISTART}} = 0
  {{TAGBL|ICHARG}} = 2
  {{TAGBL|SYSTEM}} = clean (111) surface
  {{TAGBL|ENMAX}} = 270
  {{TAGBL|ISMEAR}} = 2 ; {{TAGBL|SIGMA}} = 0.2
  {{TAGBL|ALGO}} = Fast
  {{TAGBL|EDIFF}} = 1E-6
   
dynamic:
  {{TAGBL|NSW}} = 100
  {{TAGBL|POTIM}} = 0.8
  {{TAGBL|IBRION}} = 1
 
*Same {{TAG|INCAR}} file as for {{TAG|Ni 100 surface relaxation}}, but spin polarization neglected.
 
=== {{TAG|KPOINTS}} ===
<pre>
k-points
0
Monkhorst-Pack
9 9 1
0 0 0
</pre>
 
== Calculation ==
 
*N.B.: The setup for the calculation of the "bulk" energy can be found in the ''Ni111clean_rel/bulk'' subdirectory of the tar file.
 
*The sample output for the forces should look like the following:
POSITION                                      TOTAL-FORCE (eV/Angst)
-----------------------------------------------------------------------------------
      0.00000      0.00000      0.00000        0.000000      0.000000      0.178848
      0.00000      1.44112      2.03805        0.000000      0.000000    -0.060127
      1.24804      0.72056      4.07609        0.000000      0.000000      0.004418
      0.00000      0.00000      6.11522        0.000000      0.000000      0.036384
      0.00000      1.44112      8.14905        0.000000      0.000000    -0.159523
-----------------------------------------------------------------------------------
    total drift:                              -0.000084      0.000107    -0.017457
 
*Forces are already small at the beginning (small relaxations for compact surfaces).


{{TAG|ALGO}}, {{TAG|EDIFF}}, {{TAG|ENCUT}}, {{TAG|ENMAX}}, {{TAG|IBRION}}, {{TAG|ICHARG}}, {{TAG|ISMEAR}}, {{TAG|ISTART}}, {{TAG|NSW}}, {{TAG|POTIM}}, {{TAG|SIGMA}}, {{TAG|SYSTEM}}
*For surface energy non-spin-polarized bulk nickel as reference:
**<math>\sigma^{\mathrm{unrel}} = \frac{1}{2} (-25.731 - 5 \cdot (-5.407)) = 0.65</math> eV.
**(111) surface more stable than (100) surface.


== Download ==
== Download ==
[http://www.vasp.at/vasp-workshop/examples/Ni111clean_rel.tgz Ni111clean_rel.tgz]
[[Media:Ni111clean_rel.tgz| Ni111clean_rel.tgz]]
----
[[VASP_example_calculations|To the list of examples]] or to the [[The_VASP_Manual|main page]]
{{Sur_sci}}


[[Category:Examples]]
[[Category:Examples]]

Latest revision as of 13:56, 14 November 2019

Task

Relaxation of the first two layers of a Ni (111) surface.

Input

POSCAR

 fcc (111) surface
  3.53
   .70710678  .0000000  .000000
 -0.35355339 0.6123724  .000000
   .000000    .000000  5.1961524
    5
selective dynamics
direct
   .00000000   .00000000   .00000000  F  F  F
   .33333333   .66666667   .11111111  F  F  F
   .66666667   .33333333   .22222222  F  F  F
   .00000000   .00000000   .33333333  T  T  T
   .33333333   .66666667   .44444444  T  T  T
  • Similar setup as for Ni 100 surface relaxation.
  • Again 2 of 5 layers relaxed.
  • of vacuum.

INCAR

general:
  ISTART = 0
  ICHARG = 2
  SYSTEM = clean (111) surface
  ENMAX = 270
  ISMEAR = 2 ; SIGMA = 0.2
  ALGO = Fast
  EDIFF = 1E-6
    
dynamic:
  NSW = 100
  POTIM = 0.8
  IBRION = 1

KPOINTS

k-points
0
Monkhorst-Pack
9 9 1
0 0 0

Calculation

  • N.B.: The setup for the calculation of the "bulk" energy can be found in the Ni111clean_rel/bulk subdirectory of the tar file.
  • The sample output for the forces should look like the following:
POSITION                                       TOTAL-FORCE (eV/Angst)
-----------------------------------------------------------------------------------
     0.00000      0.00000      0.00000         0.000000      0.000000      0.178848
     0.00000      1.44112      2.03805         0.000000      0.000000     -0.060127
     1.24804      0.72056      4.07609         0.000000      0.000000      0.004418
     0.00000      0.00000      6.11522         0.000000      0.000000      0.036384
     0.00000      1.44112      8.14905         0.000000      0.000000     -0.159523
-----------------------------------------------------------------------------------
   total drift:                               -0.000084      0.000107     -0.017457
  • Forces are already small at the beginning (small relaxations for compact surfaces).
  • For surface energy non-spin-polarized bulk nickel as reference:
    • eV.
    • (111) surface more stable than (100) surface.

Download

Ni111clean_rel.tgz