[lammps-users] Final replica has the highest energy in the NEB calculation

Dear Lammps users,

I am calculating the dislocation loop nucleation energy barrier. However, the final has the highest energy, as shown in the attached figure. Normally, the intermediate replica should has the highest energy.

I choose the model as initial model, which is just after the model is built using create command. The final model is just after the dislocation loop is created by displacing the related atoms.

Then 12 replicas are used for NEB calculation. I also tried 28 replicas, the result is almost the same as that of 12-replica.

The fix neb command I used is shown below:
fix 1 all neb 0.1 parallel neigh perp 1.0 end last 1.0

I adjust the last 1.0 to 10 or neb 0.1 to neb 1.0, and their results are almost the same as the original.

Could you please tell me how I can fix this problem? Thanks in advance.

Best regards,

Kevin

For a meaningful NEB calculation both initial and final configuration have to be relaxed/minimized configurations.
From your description that does not seem to be the case.

Axel.