[lammps-users] friction force calculation(compute group/group & fcm())

Hi,Steve:
   I want to calculate the friction force between two groups(atoms only have pair interaction),could you tell me which command should be adopt. I have tried compute group/group and variable fcm(),but they produce very different values. There aren't enough details about these two method in manuls,so I want to ask you for an advice, thank you!
    Yours sincerely, Xu

Compute group/group will compute only the forces
from group1 atoms on group2 atoms. Fcm will compute
the total force on a group's atoms, from all sources.

Steve

2009/5/14 许亮 <[email protected]>: