Hi, As Karpati says, you have to ensure that the parameters like ecutwfc, number of kpoints and smearing are ok, with a good system behavior and convergence, for the scf calculation. (A smaller degauss, 0.01 or less, and higher ecutwfc, 45, maybe) If your calculation is converging in the scf, you do not need to increase more the number of bands, the default increasing due to smearing it is fine. Your problem in the nscf bands calculation is probably because you are using a very high convergence threshold. conv_thr in scf calculation its a total energy like criterion... but for nscf calculation it defines indirectly, the diago_thr_init, which is the convergence criteria for eigenvalues.
For non-scf calculations: default is (conv_thr <https://www.quantum-espresso.org/Doc/INPUT_PW.html#conv_thr>/N elec)/10 With your input this values is 10⁻¹².... too low. For bands calculation it is not necessary a diago_thr_init lower than 10⁻ ⁵, if you need only the band energies. If you use a conv_thr=1e-2 or 1e-3, the problem should disappear. Regards!
_______________________________________________ Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users