Ni 111 surface high precision

From VASP Wiki
Revision as of 09:56, 14 November 2019 by Karsai (talk | contribs) (→‎Download)

Task

Calculation of the adsorption energies and the work function of a Ni (111) surface with high precision.

Input

POSCAR

 fcc (111) surface                      
   3.53000000000000     
     0.7071067800000000    0.0000000000000000    0.0000000000000000
    -0.3535533900000000    0.6123724000000000    0.0000000000000000
     0.0000000000000000    0.0000000000000000    5.1961523999999999
   Ni
     5
Selective dynamics
Direct
  0.0000000000000000  0.0000000000000000  0.0000000000000000   F   F   F
  0.3333333300000021  0.6666666699999979  0.1111111100000031   F   F   F
  0.6666666699999979  0.3333333300000021  0.2222222199999990   F   F   F
 -0.0000000000000000 -0.0000000000000000  0.3320935940210170   T   T   T
  0.3333333300000021  0.6666666699999979  0.4413539967541983   T   T   T
 
  0.00000000E+00  0.00000000E+00  0.00000000E+00
  0.00000000E+00  0.00000000E+00  0.00000000E+00
  0.00000000E+00  0.00000000E+00  0.00000000E+00
  0.00000000E+00  0.00000000E+00  0.00000000E+00
  0.00000000E+00  0.00000000E+00  0.00000000E+00


INCAR

 ENMAX = 400
    
general:
  SYSTEM = clean nickel (111) surface
  ISTART = 0
  ICHARG = 2
  ISMEAR = 2 ; SIGMA = 0.2
  ALGO = Fast
  EDIFF = 1E-6
    
special:
  LVHAR = .TRUE.
#  LVTOT = .TRUE.
  • Run a single point calculation for the Ni(111) clean surface at a higher cutoff (400eV), which is needed to compute the adsorption energy.
  • Potentials for O and C require an energy cut-off of 400eV:
    • Previous calculation for clean cannot be used as reference.
    • Recalculate with same energy cut-off.

KPOINTS

K-Points
0
Monkhorst-Pack
9 9 1
0 0 0

Calculation

Adsorption energies

  • Change of cut-off lowers total energy:
    • -25.732 eV (270 eV); -25.737 eV (400 eV).
    • Becomes more important for larger cells.
  • The adsorption energy is calculated in the following way:
    • .
    • eV.

Work function

  • We use this run also to calculate the work-function of Ni(111).
  • Use p4vasp to show the planar average of the potential:

  • Vacuum potential eV.
  • Fermi level eV. (from OUTCAR file).
  • Work function eV.

Download

Ni111clean_400eV.tgz

Back to the main page.