[lammps-users] Excluding inter-molecular interaction when using table potential

Dear lammps user,

Are there ways to exclude intermolecular interaction? I am struggling with finding the ways. Can any one give me advice?

with my best regards


I made a mistake replying to individual not to mailing list so I reattach my question. Sorry about that.

I have to simulate a model polyelectrolyte. In my system, the interaction potential contains several terms such as intermolecular interaction, bond interaction and purely repulsive interaction. First interaction acts for the inter and intramolecular interaction. Second one, bond interaction works for bonded interaction. However, for the purely repulsive interaction, I need to exclude the intermolecular interaction between other polyelectrolyte beads and it should exclude 1-2 pair interaction. If I use neigh_modify to exclude intermolecular interaction, then it is excluding all molecules’ intermolecular interaction, as far as I know. Are there ways to exclude intermolecular interaction and exclude 1-2 pair interaction just for the purely repulsive interaction?

With my best regards

2021년 4월 13일 (화) 오전 3:42, 이영규 <[email protected]>님이 작성:

1-2 interactions will be excluded with the proper choice of settings for “special_bonds”.
for the repulsive contribution I see two possible approaches: 1) write a custom pair style that requires not only the distance to be smaller as the cutoff but also the molecule ID for both atoms to be the same for interactions to be applied 2) give each molecule its own set of atom types then you can define inter- and intramolecular interactions via pair_coeff (you probably need to write a script to do this if you have many molecules).