Hello,

I’m running NEB calculations using VASP for interstitial diffusion, but my job seems to be stuck at the 84th iteration. There are no error messages or issues in the output files, and the job is still running, but it’s not progressing. I am using 2 nodes with a total of 60 cores. Another job using the same resources with the climbing method ran perfectly running fine, so I’m unsure why this one is stuck.

Additionally, another job for vacancy diffusion got stuck at the 869th iteration, with the climbing method turned on. The strange thing is, I previously studied vacancy diffusion with the same INCAR parameters and the same number of nodes and cores, and that job ran perfectly fine. However, something seems to be going wrong with this particular job.

Here is the INCAR file:

Global Parameters

ISTART = 0

ISPIN = 2 # Spin polarized DFT

ICHARG = 2 # If ISTART is zero, self-consistent, GGA/LDA band structure

LREAL = A # Projection operators: automatic

ENCUT = 300 # Cut-off energy for plane wave basis set, in eV

PREC = Normal # Precision level

Electronic Relaxation

ISMEAR = 0 # Gaussian smearing; metals: 1

SIGMA = 0.05 # Smearing value in eV; metals: 0.2

#NELM = 60 # Max electronic SCF steps

NELMIN = 5 # Min electronic SCF steps

EDIFF = 1.0E-05 # SCF energy convergence; in eV

EDIFFG = -0.05

Ionic Relaxation

NSW = 1800 # Max ionic steps

#IBRION = 2 # Algorithm: 0-MD; 1-Quasi-New; 2-CG

ISIF = 2 # Stress/relaxation: 2-Ions, 3-Shape/Ions/V, 4-Shape/Ions

#POTIM = 0.5

NEB Parameters

ICHAIN = 0 # NEB flag for VTST package

IMAGES = 5 # Number of intermediate images, end images not included

SPRINGS = -5 # Spring constant for the elastic band

LCLIMB = .FALSE. # Climbing method flag, turned off for this run

IOPT = 3 # 3 for SS-NEB; 3 → 2 → 1 for CI-NEB

IBRION = 3 # Required for VTST

POTIM = 0 # Required for VTST

ALGO = Normal

NCORE = 10

Has anyone encountered similar issues where the job gets stuck without errors? Could there be any particular reason for this behavior? Any suggestions to troubleshoot or optimize the calculation settings would be appreciated.

Thanks in advance!