problem with special_bonds

Hello, I am working with the buck/coul/long/cs potential and a core-shell model, so I want to remove the Coulomb interaction between all the cores and their own shells. To do that, I am using the command: special_bonds coul 0.0 1.0 1.0

but if I print the forces over each atom of the system there is no difference between using the command or not. I think I am doing something wrong but I don’t know what. Can you tell me what I have to do? I leave here my input and the file with the coordinates, which is the groung state with a shell displaced by me to not have zero force. In both cases (with and without the special_bonds command) I obtain this force for the first shell (second atom): 2 3 -2.20213 -3.37996 -6.88967

Thank you very much for your attention.

Juan

input file

Hello, I am working with the buck/coul/long/cs potential and a core-shell
model, so I want to remove the Coulomb interaction between all the cores and
their own shells. To do that, I am using the command: special_bonds coul
0.0 1.0 1.0
but if I print the forces over each atom of the system there is no
difference between using the command or not.

that is because the default setting is: special_bonds lj/coul 0.0 0.0 0.0

so if your system only has the core-shell bonds, then what you see is
the expected behavior.

axel.