A warning about the Compute force/tally command

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1

Hello,
In my nanoindentation simulation, I want to calculate the resistance force of the indenter.
The interaction between the graphene membrane and the indenter is described by LJ potential.
However, a warning occurs, “Compute force/tally used with incompatible pair style (…/compute_force_tally.cpp:75)”
I have read the manual and learned about the limitations of this command. I still can not find the source of the warning.
Although the model can continue to run, I am not sure whether the result will be affected by the warning.
Then ,I tried to use another command（compute group/group） to calculate the resistance force. Fortunately, there were no warnings.
But, I still want to know what’s wrong with the Compute force/tally command.
Here is my original script ( LAMMPS version:LAMMPS 64-bit 29Jun2018-MPI)

clear
log indent.log
read_restart model.restart
reset_timestep 0
neighbor 3.0 bin

pair_style hybrid/overlay rebo lj/cut 6
pair_coeff * * rebo CH.airebo C NULL
pair_coeff 1 2 lj/cut 0.002 3.4
pair_coeff 2 2 none

timestep 0.001
thermo 200

fix 1 boundary setforce 0.0 0.0 0.0
fix 3A membrane nvt temp 1 1 0.1

velocity bullet set 0.0 0.0 -0.4 units box
fix 3B bullet rigid molecule
fix 3C bullet setforce 0.0 0.0 0.0

compute a2 indenter force/tally membrane
thermo_style custom time c_a2
run 65000

Best regards.

2

you get the warning from compute force/tally because there is a manybody potential used.
the check is a global one and not checking, whether you are only tallying forces from a compatible subset.

axel.

3

thanks, I got it.