Hi,

I am woking on N-doped graphene (49 C and 1 N) and did convergence check to see the optimal (or the best) K and Encut values to be chosen for the minimization. I got the following numbers which show some ups and downs in the total energy written in the OUTCAR (energy sigma->0). Any help to figure it out? I presume, higher K-point and EnCut should provide better values.

400 -459.86236853 -459.8575553 -459.8566265

450 -459.52324679 -459.5181853 -459.5175918

500 -459.41923826 -459.4143076 -459.4138069

550 -459.43005966 -459.4251268 -459.4245913

600 -459.53038956 -459.5255936 -459.5249424

I read in the forum something we should substract kinetic energy erorr from the total energ before checking the values? I got the following the values for Kinetic Energy Error. That means I have to multiply 0.0057 x 49 and 0.0103 one time for each other. This was not clear in the forum answer.

kinetic energy error for atom= 0.0057 (will be added to EATOM!!)

kinetic energy error for atom= 0.0103 (will be added to EATOM!!)

the INCAR for Single point energy on the optimized geometry is shown below to check whether there is any error or not

# Basic setup:

SYSTEM = N-doped Graphene

ISPIN = 2

NCORE=24

KPAR=5

LSORBIT = .FALSE.

# not using Hubbard U

# Accuracy controls:

# PREC = High

ENCUT = 600

# Electronic loop controls:

ALGO = Fast # Fast (Davidson + RMM-DIIS)

EDIFF = 1E-7

NELMIN=15

NELM=60

#TIME = 0.400000

ISMEAR = 2 # 2nd order Methfessel-Paxton method

SIGMA = 0.2 # eV

# NBANDS = 144

# Relaxation control:

IBRION = -1

NSW = 0

POTIM = 0.2

ISIF = 2 # Ions Cell Volume

EDIFFG = 1E-5

# Properties:

LCHARG = .TRUE.

LWAVE = .TRUE.

# LVTOT = .FALSE. #Default False

# LVHAR = .FALSE.

I appreciate your help

Thanks

Rajesh