Calculating bond energy in reaxFF

Dear users

I am using pairstyle reax/c and wish to calculate the bond energy between two atoms forming a bond. I have identified the atoms forming a bond with fix reac/c/bonds and proceeded to compute the potential energy during rerun. The following is my input script

Dear users


I get the following error - ERROR: Pair style does not support compute

​you get this error, because compute group/group only works for pair-wise
additive potentials and ReaxFF does not classify. on the contrary.

Is there a better way to calculate bond energy between two atoms forming
bonds in reaxFF.

​there are issues with your approach in general.

you have to decide whether you want to know the static potential energy
​barrier/difference for the reaction (i.e. at 0K) or the free energy
barrier/difference (i.e. including entropy contributions).

for the former, you could do a NEB calculation and find the lowest
potential energy path across from state A to B

for the latter, you need to do some kind of statistical sampling, e.g. via
metadynamics, umbrella sampling, ABF and so on along a suitably chosen
reaction coordinate, e.g. the bond length.
just doing "rerun" on a single event of a single trajectory is useless in
this context and does not provide relevant information.

both approaches are supported by LAMMPS.