calculation pure electric force

Dear everyone

I used pair_style buck/coul/cut and fixed electric field(efield fix) for the applied external electric field.

I tried to the calculation of Electric force for each element by this command:

write_dump all custom Force.lammpstrj x y z fx fy fz

But it includes force due to Buckingham potential, Coulomb potential, and external electric field.

Do you have any idea to calculation pure electric force that includes Coulomb potential and external electric field without Buckingham potential?

Best regards

the forces in the dump command are always all forces computed according to all entities that add to forces. you cannot decompose that in as much as you cannot tell from the number 10 whether it was computed from the sum of 5+5 or 4+6 or …

please have a look at the rerun command which allows to compute forces (and all kinds of properties) with different settings for a prerecorded trajectory, e.g. using pair style coul/cut instead of buck/coul/cut.