> Indirect (band structure attached) > > R Roberto: sorry for this question, but are you sure that this band structure corresponds to your 64-at calculation? I'd expect much more bands and much less dispersion with 64 at. supercell. (I did not count the bands per energy interval, though, so I might be wrong). Anyway: how does your total DOS look like?
Best regards Andrei Postnikov > > In date 4/3/11 15:23:46, karim rezouali wrote: >> Dear, >> >> Is the material under study (ie, bulk amorphous silicon) has a direct >> electronic gap or not? >> >> Karim >> >> >> Hello, >> >> I calculated the band structure of bulk amorphous silicon (64 atoms >> tetrahedrically coordinated). I found an HOMO-LUMO band gap of about 0.7 >> eV. Then I performed the OpticalCalculation, but I have that the >> resulting >> imaginary dielectric function has a peak at E<0.7. How is this possible? >> I >> expect that each valence-to-conduction transition must be larger than >> the >> bang-gap! >> >> Roberto >
