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Fcc Si bandstructure

Contents

Computation of the bandstructure in fcc Si along L-Γ-X-U and K-Γ.

Input

POSCAR

```fcc Si:
3.9
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 Si
ICHARG = 11 #charge read file
ENCUT  =    240
ISMEAR = 0; SIGMA = 0.1;
LORBIT = 11
```

KPOINTS

```k-points for bandstructure L-G-X-U K-G
10
line
reciprocal
0.50000  0.50000  0.50000    1
0.00000  0.00000  0.00000    1

0.00000  0.00000  0.00000    1
0.00000  0.50000  0.50000    1

0.00000  0.50000  0.50000    1
0.25000  0.62500  0.62500    1

0.37500  0.7500   0.37500    1
0.00000  0.00000  0.00000    1
```
• k points along the line ${\displaystyle L-\Gamma -X-UK-\Gamma }$.
• 10 points per line.
• Keyword line to generate bandstructure.
• In reciprocal coordinates.
• All points with weight 1.
• Example bandstructure should look like this:

CHGCAR

This calculation needs a converged charge density as input (ICHARG=11). You may use the CHGCAR file of the fcc Si DOS example.

CALCULATION

• To copy the self-consistent charge density of example fccSidos to your current working directory, type:
```cp ../fccSidos/CHGCAR .
```
• You must do this otherwise VASP can not read the CHGCAR and will terminate.
• To plot the bandstructure use p4vasp:

Mind: For this calculations you need the CHGCAR file of the fcc Si DOS example.