Free End NEB Calculation in LAMMPS

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1

Dear all,

Have anyone performed free end NEB calculation using LAMMPS? During free end NEB calculation one end state is allowed to swing on an iso-energy surface.

Best,

Q
J

2

Both end states will go to their energy minimum, wherever that
is, so if one of the end states is not initially at a minimum,
it is free to move.

Steve

3

Thank you Steve. But this is slightly different from what I mean by free end. For problems like dislocation nucleation under certain stress level, ā€œfree end NEBā€ method is generally used. In this method, a final state(actually is an unstable state) with energy slightly lower than that of saddle point is used. During NEB calculation, the energy of this final state is constant(this means it is only allowed to move on the iso-energy surface) but finally it will be on the minimum energy path. In such a way, a stable elastic band can be ensured and the number of replicas required can also be reduced. The current version of LAMMPS actually requires both end states be their energy minimum. If this ā€˜free endā€™ method can be included, it should be more efficient and useful.

1 Like
4

If you know how to add it to the existing NEB, then go for it.

Steve