My Community

I cannot run full relaxation (ISIF = 3), I found error message:

Error EDDDAV: Call to ZHEGV failed. Returncode = 78 510

This error didn't occur for using ISIF = 2 or 4

This is my INCAR file :

ISTART = 0
ICHARG = 2
ISMEAR = -5
NSW = 199
ISIF = 3
IBRION = 2
PREC = High
NEDOS = 501

I have 17 atoms in POSCAR

Thank you very much

most probably, the error occured because relaxation lead to some unreasonable cell geometry (volume, in this case)
please check
1) if your system really is non-metallic (ISMEAR!)
2) if your input cell (volume!) and/or the volumes obtained from the first relaxation steps were reasonable. (grep vol in OUTCAR
to do so). It may help to decrease POTIM in order to avoid over-shooting relaxation effects in the first geometry optimization steps.
Please mind that for large changes in volume/shape the geometry has to be pre-converged (do a few ionic steps ) and re-started from the CONTCAR of that pre-converged geometry, in order to provide reasonable basis set sizes for the
final steps.