structural optimization of monolayer

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liaqat_ali
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structural optimization of monolayer

#1 Post by liaqat_ali » Tue Jan 16, 2024 1:31 pm

I am trying to optimize 4*4*1 supercell of monolayer, the following is my input file, the POSCAR contain 33 atoms, KPOINTS 5 5 1, but still, it does not optimize after it stop.
> ISTART = 0
> ALGO = Fast
> EDIFF = 1.0E-5
> EDIFFG = -0.02
> POTIM = 0.3
> ENCUT = 400
> IBRION = 2
> ISIF = 2
> ISMEAR = 0
> LREAL = Auto
> LWAVE = .FALSE.
> NSW = 500
> PREC = Accurate
> SIGMA = 0.05
> GGA = PE
> NPAR = 1
> ISYM = 0
> IVDW = 11
> #LORBIT = 11
> LCHARG =. FALSE.

alexey.tal
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Re: structural optimization of monolayer

#2 Post by alexey.tal » Tue Jan 16, 2024 1:59 pm

Dear liaqat_ali,

Could you please provide all relevant input and output files for your calculation according to the forum guidelines.

liaqat_ali
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Re: structural optimization of monolayer

#3 Post by liaqat_ali » Tue Jan 16, 2024 2:22 pm

New folder.zip
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alexey.tal
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Re: structural optimization of monolayer

#4 Post by alexey.tal » Tue Jan 16, 2024 2:35 pm

I am not sure I fully understand the question. Could you please explain in more detail what seems to be the problem?
The provided OUTCAR only contains 11 ionic iterations, but the relaxation might require much more steps.

liaqat_ali
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Re: structural optimization of monolayer

#5 Post by liaqat_ali » Tue Jan 16, 2024 2:43 pm

The problem is that the calculation stops after many hours and show the optimization is completed, but when check the structural energy in RUNLOG file its not complete. so, like what parameters I should change in input file that it run properly optimize.

alexey.tal
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Re: structural optimization of monolayer

#6 Post by alexey.tal » Tue Jan 16, 2024 2:54 pm

Could you provide the OUTCAR file for this calculation? How many ionic steps were performed? What exactly suggests that the structure is not fully optimized?
If you would like to optimize your structure further, you should increase NSW and use more stringent convergence criteria, i.e., EDIFFG.

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