[lammps-users] Measuring angles


I am attempting to simulate a polymeric system with LAMMPS and would like to see a distribution of angles (or average value) broken down by angle type, ie: my system contains 10 angle types, I want to see a histogram of the distribution of angles of angle type 5 averaged over the last 100 picoseconds of my simulation (numbers are arbitrary).

I have looked at the documentation on the “compute angle/local command”, but cannot select a specific angle. Likewise, the “compute property local” command doesn’t seem to output an angle. My intent was to feed the output of whatever command I end up using into “fix ave/histo” to get a histogram.

Any ideas on how to get the angle distribution over time for a specific angle type in my system?

Thanks in advance (please let me know if you need more info or clarification),
-Greg Larsen

1) create a group "foo" of the atoms involved in angles of type 5
2) compute list foo angle/local theta
3) fix 1 all ave/histo 100 1 100 0.0 90.0 10.0 c_list file out.histo

2) will calculate the angles of type 5, 3) will histogram them
I haven't tried these commands, but that's the idea.