[lammps-users] Query regarding total energy per atom.

Dear Lammps Users,

I am having a little problem in calculating total energy per atom. Basically, what I want to calculate is K.E. + E_Vdwl+ E_Coul+ E_long per atom. Now, using dump_custom command, I can print out the first three, i.e., ke and epair (e_vdwl+e_coul) but it seems that elong/atom is not added in that command.

So, my question is

  1. how much sense does it make to calculate E_long for a pair of atom e_long(i,j) and summing over all js in order to calculate e_long(i)?
  2. How should I go about it?
    Possible Approach:
    There is a function single() in pair_lj_cut_coul_long.cpp (the pair_style I am using) which calculates the total force (forcevdwl and forcecoul). Should I extract that forcecoul and multiply by the distance (i,j) to have to total columbic energy (e_coul+e_long)?
    Any other suggestions to calculate the e_long for each atom would be highly welcomed.

Thanks in advance

Regards,
Vikas

Elong is computed in pppm.cpp (or Ewald). I don't know what
the definition of per-atom Elong is, since it isn't computed and
summer over atoms, but for the entire system in reciprocal space.

Steve