Hello,

I am running MD simulation with NPT ensemble using VASP. I refer the community forum questions and find the information, how to get the value of external pressure from NPT run OUTCAR file,

grep "Total+kin" OUTCAR| awk 'BEGIN {p=0.} {p+=($2+$3+$4)/3.} END {print "pressure (kB):",p}'

I used this command, but its printing only one pressure value, I am not clear whether its average external pressure during the run or last step pressure?

How to get the value of external pressure at each MD step? I think we need these values to check the convergence of set external pressure?

Here is my INCAR file:

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Graphene !title

Starting parameters:

ISTART = 0 #0-new, 1- Continuation job , 2-samecut

NWRITE = 0 ! verbosity for OUTCAR

LWAVE = .TRUE. ! write WAVECAR?

LCHARG = .FALSE. ! write CHGCAR?

LVTOT = .FALSE. ! write LOCPOT?

Electronic relaxation

ALGO = Accurate ! coupled to IALGO

IALGO = 48 ! 8: conjugate gradient, 48: DIIS

ENCUT = 520 ! kinetic energy cut-off (see Sholl/Steckel Ch 3.2)

ISMEAR = 0 ! electron smearing method. -1: Fermi 0: Gaussian 1..N: Methfessel-Paxton

SIGMA = 0.05 ! smearing parameter (see Sholl/Steckel Ch 3, p 11.)

ISYM = 0

PREC = normal ! coupled to ENCUT

LREAL = auto ! work in real or recipricol space (see Sholl/Steckel Ch 3.1)

EDIFF = 1.0E-5 ! elec. struc. converged when diff. btwn subsequent steps is less than this.

ISPIN = 2 ! spin polarization? 1=no, 2=yes.

LVDW = .TRUE.

IVDW = 1

NCORE = 4

Ionic relaxation

NSW = 2000

IBRION = 0

ISIF = 3

POTIM = 0.5 ! scaling constant

EDIFFG = 1.0E-4 ! geom. converged when all forces are lower than abs. value (eV/Ang

MDALGO = 3

PSTRESS = 0.05

LANGEVIN_GAMMA = 10 10 10

LANGEVIN_GAMMA_L = 1

PMASS = 35

TEBEG = 298 ; TEEND = 298 ! temperature

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Any help is really appreciated.

Thanks in advance,

Sahida

Ph.D. Candidate

Simon Fraser University

13450 102 Avenue, Surrey(BC)-V3T 0A3

CANADA