My Community

Dear sir,
I am trying to run a perovskite structure MAPbI3 in vasp. But the job is not running and coming out. The INCAR file that I am using is:
SYSTEM = MAPbI3

PREC = Normal
ENCUT = 400
IBRION = 2
NSW = 200
ISIF = 4
NELMIN = 2
EDIFF = 1.0e-06
EDIFFG = -0.02
VOSKOWN = 1
NBLOCK = 1
NELM = 60
ALGO = Normal (blocked Davidson)
ISPIN = 1
INIWAV = 1
ISTART = 0
ICHARG = 2
LWAVE = .FALSE.
LCHARG = .FALSE.
ADDGRID = .FALSE.
ISMEAR = 1
SIGMA = 0.2
LREAL = .FALSE.
KSPACING = 0.12
KGAMMA = .FALSE.
RWIGS = 0.73 0.75 0.77 0.32

This file is working for my other structures having C,H,N,O atoms.
For a test I replaced 1 of atom in my other structures with Pb. Now It is not not running.Similiar thing is happening with Sn atom.
Is there anything specific that I need to learn if using Pb or Sn atom.

Thanking you,

Hi.

Can you tell at which point the calculation stops and what is (if any) the error message?

I don't know if it can help, but I had many problems in converging my ground state calculations and I finally meanged.
1) I observed that changing the ALGO falg can make some difference. Get a look on possible alternatives of ALGO=Normal and give a try.
2) I also observed a strong dependence of the convergence on the pseudopotential used, but I don't think it can be your problem since you are likely using the lighter pseudo.
3) If your system is a semiconductor you can try to split the calculation into two steps: a first step including only occupied states (attention: NBANDS is modified according to NPAR). Then you can make a second calculation including empty bands if needed (optics, band structure, dos) using ALGO=EXACT. In my case this procedure worked perfectly even if it's more time-consuming.

Good luck!

Dear sponza,
Thanks for the response. The problem is solved. I have deleted that RWIGS line as it will be automatically included from the POTCAR file. Now all the jobs are running smothly.