pair interaction energies and forces


I am simulating a box of water molecules, and I would like to output the pair interaction force and energy distribution over radius between O-O, O-H, and H-H interactions. I believe this can be done using something like:

compute ID GROUPID pair/local eng force
dump ID GROUPID local 1000 name.dump index c_ID[1] c_ID[2]

However, I am not getting a reasonable output from this. Can someone explain to me how this is properly done? Should a compute be done separately for each interaction (OO, OH, HH) corresponding to the GROUPID?


You can use compute pair/local and dump local to

output the pairwise force/energy between all (or a subset)

pairs of atoms. Compute property/local can be added

to list additioanl values in the dump file, like the types

of the 2 atoms in each pair.

You can then post-process to create distributions as a function

of radius. Or possibly use fix ave/histo to do that on the fly.