Dear all, At the last workshop, Steve mentioned that using the pair_style hybrid is not computationally efficient, as LAMMPS builds multiple neighbour lists for every pair style. Suppose I want to use the same cutoff for all the pair styles, what is the best strategy to modify LAMMPS in order to build the neighbour list just once and use it for every pair style? This question is …

Dear all, I’m trying to develop LAMMPS interface to my new machine learning interatomic potential. The potential is pairwise in nature between molecules. Hence to calculate energy (and forces on atoms) I need to know positions of all atoms in both molecules at an instant (say 4 atoms for H2-H2 pair). The atoms in a molecule are permanently bonded (bond_style) and rigid (fix shake…

Dear LAMMPS Users I’m trying to calculate the binding energy between two graphene layers using an LJ potential. I realize there are more accurate descriptions but I’m doing this as an initial step in my research. My problem is in the value of binding energy between the two layers, it does not yield the epsilon value of the LJ potential which is the minimum energy. The code is easi…

I’m using lammps via the C-API library with a no-MPI compilation. I go through a sequence of setting the configuration via lammps_command("change_box ....") and lammps_scatter_atoms(... "x"....), then lammps_command("run 0") to do the energy evaluation. I’ve been getting “Lost atoms” errors from this sequence for one particular configuration. Can anyone explain how this could b…

Hi there, I’m working on simulating gas diffusion within polymer materials and I’m seeing bizarre results that I can’t quite figure out with just the manual or past forum posts. I’m attaching the inputs I’ve been using at the bottom of this post. I’m using the OPLS force field to represent my polymer systems and the TraPPE potential to represent nitrogen gas. I understand that th…