Germanium's Band Structure

[hat343]

Hi,

I'ld really appreciate if someone can tell me how to calculate the band structure of germanium. I have done a self consistent calculation using the following KPOINTS:

Ge
0
Monkhorst pack
2 2 2
0.00 0.00 0.00

I then used the high symmetry points as given in Hands On 2 for silicon:


kpoints 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

But these dont seem to be producing the right structure! I am just a beginner and would be glad if someone can suggest the right form of the KPOINTS to be used!

Many thanks!!

[metosa]

Dear hat343,

In Handson2 2_1_fccSi folder, the POSCAR was given like


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

But correct POSCAR should be like

fcc Si:
3.9
0.5 0.5 0.0
0.0 0.5 0.5
0.5 0.0 0.5
2
Direct
0 0 0
0.25 0.25 0.25

Have you noticed this ?

In addition, 2 2 2 KPOINTS are really insufficient. Why don't you try more KPOINTS such as 11 11 11 ?

[hat343]

Metosa, many thanks. But one more naive question if I'm allowed why 11x11x11 not 10x10x10 for example??!

[metosa]

I haven't tested it. You can test it by yourself. Prepare a script which loops the kpoints from 2 to 20 and compare their energies....

[metosa]

I haven't tested it. You can test it by yourself. Prepare a script which loops the kpoints from 2 to 20 and compare their energies....