I am asked to discuss the band structure of diamond. I saw the band structure of diamond has 4 filled valence bands and then 4 conduction bands. Silicon, the same.
The Attempt at a Solution
I'm feeling really silly because I don't understand why it is that way. Each carbon in diamond has a filled 1s and then 4 half filled sp3 orbitals. Therefore, I expect a filled valence band arising from the 1s orbital, and 4 other bands arising from the sp3 orbitals which in turn cross the fermi level, not 8 bands, 4 below and 4 above with a band gap.
EDIT: Don't answer yet, I'm updating the post.