There is no description for electric_potential field in "fix_modify AtC fields" command

Hello LAMMPS developers,

Although I can run a simulation with the command “fix_modify ATC fields add electric_potential” (LAMMPS 3 Mar 2020) without any problem, there is no description for the electric_potential field. Can you please add some information about it, for example, what the unit is?

Best,
Duc Tam

Please note that the project that funded the development of the AtC package does not exist anymore for quite some time, so there is no active development and thus nobody that would be around to do such updates. First order approximation of the unit would be the same units if you would compute the electrostatic potential of the (charged) atoms in your system, which will depend on the choice of units in LAMMPS (units command — LAMMPS documentation). If that seems inconsistent, the second place to look for information would be the comments in the source code (mostly in the lib/atc folder).

For more specific questions, you can try contacting the AtC package developers. Most of them will likely have retained their email addresses, which should be mentioned in the source code and README files related to the AtC package.