Please post to the list, not to me.
In your first email you said you were using
buck/coul/long. What I was telling you
is that potential includes an erfc() term to damp
the short-range Coulombics. Also you must
you a KSpace solver (e.g. Ewald, PPPM) when
you use a pair style with “long” in the name.
If you want to just use buck/coul, then both
those things change.
Steve