[Pw_forum] Regarding Band Structure in primitive and conventional cell

[David Foster]

Dear Users
Apologize for this simple question. Please guide me:
I have used Si bulk for calculating its band gap. I used two approaches for doing it. One with ibrav=2 and working with primitive cell, and the other with ibrav=0
and working with its conventional cell.
For primitive I used following high-symmetric points:
G: 0.0 0.0 0.0
X: 0.5 0.0 0.5
L: 0.5 0.5 0.5
K: 0.375 0.375  0.75

and for conventional:
G: 0.0  0.0  0.0
X: 0.5  0.0   0.0
M: 0.5  0.5  0.0
R: 0.5  0.5  0.5

I got two different band structures.Conventional cell can be supposed as a supercell of its primitive, so, in the case of conventional, I thought I get only folded
band structure. I have attached them.

Regards

David Foster

Ph.D. Student of Chemistry
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