Dear LIANG Xiongyi,
Some answers:
- Yes, one needs fixed occupations, because the implementation in PH is
for non-resonant Raman scattering; the formalism in metallic systems is
much more involved, there are some recent developments in the Quantum
ESPRESSO Community at least by Michele
Dear QE users,
As far as I know, when using ph.x to calculate raman spectrum. We should use
fixed occupation and LDA in scf, right?
However a error occur (charge is wrong, smearing is needed ) when I use fixed
occupation in scf calculation because of my system is odd electrons.
what should
