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Speeding up calculation

Posted: Tue Nov 20, 2018 4:33 pm
by Hopper1313
Hello all,

I've been trying to run some cNEBs for compression of a methylthiolate species between Cu(100) slabs. However, the calculation seems to be tremendously slow (10+ days with 6 nodes 12 cores/node). Is there anything in the INCAR here that I can change to speed up the process?


SYSTEM = cNEB MeS/Cu(100) compression

PREC = Normal
ENCUT = 400
ALGO = Fast
NELMDL = -3
LREAL = Auto
#LWAVE = .FALSE. # do not write WAVECAR file

ISMEAR = 2
SIGMA = 0.4

IMAGES = 12 # number of images, forces NEB method
LCLIMB = .TRUE. # use climbing image method
IOPT = 3 # Q-Min, relaxation method
IBRION = 3 # tell VASP to do MD
POTIM = 0 # tell VASP zero time step
SPRING = -5 # spring constant for images, >0 images don't move
# along path

NELMIN = 8 # do a minimum of four electronic steps
EDIFF = 1E-5 # high accuracy
EDIFFG = -0.03 # accuracy of ions
NSW = 1000 # 1000 ionic steps in ions

LPLANE = .TRUE.
LSCALU = .FALSE.
NSIM = 4
NCORE = 6


I based my INCAR off the work by a previous group member. He was using an older version of VASP, so I had to change a few parameters.

Thanks in advance!