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Hello,
This is probably a very simple answer but here is my question.
When performing a GW calculation, the code outputs a series of information (which includes the GW energies)
starts with --- k = (k-point)
Band E_0 ... ... ... E
for gwcalctyp<10: the last column is E and corresponds to the GW energy
then it describes the bandgap from DFT and then GW

for gwcalctyp>10 after the 1st iteration:
starts with --- k = (k-point)
Band E_lda ... ... E(N)_pert E(N)_diago
during the second tutorial on GW, it says that the last column provides the energy, but the band gap calculated right after this section corresponds to the energies given by E(N)_pert

So what are the updated GW energies(maybe iteration dependent?), the column labeled E(N)_pert or the column E(N)_diago?

I ran 2 calculations to test, one with gwcalctyp=2 and one with gwcalctyp=12,
for =2, the GW energy was labeled with E (as expected)
for =12, the GW energy was contained in E(N)_pert after the 1st iteration.
does this change for the hybrid approach when gwcalctyp=125?

E(N)_pert is the pertubatively calculated quasi particle energies at the N-th iteration step and
the column E(N)_diago is the exact quasi particle energy (at the N-th iteration step) by performing
an exact diagonalization of the subspace of quasi particle Hamiltonian.

Example :

Band E_lda <Vxclda> E(N-1) <Hhartree> SigX SigC[E(N-1)] Z dSigC/dE Sig[E(N)] DeltaE E(N)_pert E(N)_diago

60 0.634 -16.482 0.634 17.116 -7.786 -7.136 1.000 0.000 -14.922 1.560 2.194 2.229

60 0.634 -16.482 2.229 16.172 -7.273 -7.280 1.000 0.000 -14.553 -0.610 1.619 1.630

60 0.634 -16.482 1.630 16.566 -7.672 -7.198 1.000 0.000 -14.870 0.066 1.696 1.708

LUCA