PBE SOC ZERO KPOINTS ERROR

[rishikanta_m]

Hi,

I would like to calculate the MBJ band gap with SOC for my structure.
The calculation with PBE-SOC with ZERO KPOINTS runs comfortably in the beginning and then after so many iterations, it crashes or stops. I could not sort out the issue. Please advise.

[alexey.tal]

Dear rishikanta_m,

From your question I understood that you are interested in finding the band gap with MBJ functional, but you did not select the MBJ functional in your INCAR.
Before doing a calculation with zero-weight k-points, you should do a SCF calculation with a regular k-points grid and add zero-weight k-points in a subsequent non-self-consistent calculation (see detailed instructions here and here).
Are you able to reach the convergence with the regular grid?

[rishikanta_m]

Yes, I achieved convergence with regular grid.
As you mentioned, the MBJ requires WAVECAR from PBE-SCF calculation (regular k-grid with zero-weighted k) to start the calculation.
The attachment, which I have earlier posted belongs to PBE-SCF regular k-grid with zero-weighted k.
The issue is with this calculation with the inclusion of SOC. The calculation is stopped after 24 hours of calculation due to issue, mentioned in vasp.out. I am not able to comprehend the cause of the error.

[alexey.tal]

So if I understood you correctly, you were able to achieve the convergence for an SCF calculation without zero-weighted k-points. But in the attached files, the PBE calculation with zero-weight k-points starts from scratch (ISTART = 0 and ICHARG = 2). Have you tried starting you calculation from a previously converged charge density?

[rishikanta_m]

No, I have not started from a previously converged charge density.
So, to start the PBE calculation with zero-weight k-points from there, will ISTART = 0 and ICHARG =1 work? What else parameters need to be provided?

[alexey.tal]

Since you are interested in the band gap calculated with the MBJ functional, you should restart your calculation from the WAVECAR file, i.e., set ISTART = 1 and ICHARG = 0.