I did QP-GW bandstructure calculation for my structure to find the band gap. I have the following questions-

1.In the report file I get the following bandgap values. I am confused which one represents the correct QP-GW bandgap.

2.And the indirect gap between k-points mentioned are 3 and 2. Is it CBM 3 and VBM 2 or vice versa?

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```
[X] Direct Gap : 1.547477 [eV]
[X] Direct Gap localized at k-point : 10
[X] Indirect Gap : 1.347931 [eV]
[X] Indirect Gap between k-points : 3 2
[Hartree-Fock] Direct Gap : 5.565401 [eV]
[Hartree-Fock] Direct Gap localized at k-point : 10
[Hartree-Fock] Indirect Gap : 5.347683 [eV]
[Hartree-Fock] Indirect Gap between k-points : 10 2
```

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```
[X] Direct Gap : 1.547477 [eV]
[X] Direct Gap localized at k-point : 10
[X] Indirect Gap : 1.347931 [eV]
[X] Indirect Gap between k-points : 3 2
[K+QP] Direct Gap : 2.687685 [eV]
[K+QP] Direct Gap localized at k-point : 10
[K+QP] Indirect Gap : 2.496317 [eV]
[K+QP] Indirect Gap between k-points : 10 2
```

5. And is the exciton binding energy is difference between the QP-GW bandgap - 1st exciton energy? Is the 1st exciton energy the direct bandgap from BSE, or the energy of the exciton with the highest oscillator strength?

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```
E/ev[1] EPS-Im[2] EPS-Re[3] EPSo-Im[4] EPSo-Re[5]
```

Regards.