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# Partial DOS of CO on Ni 111 surface

Calculation of the work function and partial DOS of a CO@Ni (111) surface, adsorbed on top.

## Input

### POSCAR

Ni - (111) + CO ontop
3.53000000000000
0.7071067800000000    0.0000000000000000    0.0000000000000000
-0.3535533900000000    0.6123724000000000    0.0000000000000000
0.0000000000000000    0.0000000000000000    5.1961523999999998
5   1   1
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  0.3330391292438326   T   T   T
0.3333333300000021  0.6666666699999979  0.4445422014835692   T   T   T
0.3333333300000021  0.6666666699999979  0.5402025044116211   T   T   T
0.3333333300000021  0.6666666699999979  0.6031536532245922   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
0.00000000E+00  0.00000000E+00  0.00000000E+00
0.00000000E+00  0.00000000E+00  0.00000000E+00


N.B.: this POSCAR is essentially the result (CONTCAR file) of the relaxation performed in the CO on Ni 111 surface example.

### INCAR

general:
ENMAX = 400
SYSTEM = CO adsorption on Ni(111)
ISMEAR = -5
ALGO = Fast

LDOS:
LORBIT = 11

workfunction:
IDIPOL = 3
LDIPOL = .TRUE.
LVHAR = .TRUE.
#  LVTOT = .TRUE.

• For the calculation of the DOS we use a tetrahedron method with Blöchl corrections (ISMEAR=-5).
• By setting LVHAR=.TRUE. the Hartree part of the local potential is written to the file LOCPOT.
• By setting LVTOT=.TRUE. the total local potential is written tot the file LOCPOT.
• By setting IDIPOL=3 dipole corrections in the direction of the third lattice vector are enabled.
• We have active dipole corrections to potential (=dipole layer).

### KPOINTS

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


## Calculation

### DOS

• The lm-decomposed DOS helps to analyze the bonding:
• CO $5\sigma ,1\pi ,2\pi ^{*}$ bonds.
• From comparison with substrate LDOS:
• Hybridization with Ni-$d_{3z^{2}-r^{2}}$ .
• No interaction with $d_{xy}$ due to symmetry.

### Work function

• The planar average of the potential for this example should look like the following:
• $\epsilon _{\mathrm {F} }=1.65$ eV (from OUTCAR file.
• Vacuum-potential at 8.24/6.77 eV: $\Phi _{\mathrm {CO} }=6.58,\Phi _{\mathrm {clean} }=5.11$ eV.
• Too small result for clean surface due to too small vacuum ...