[lammps-users] How to get interaction force using compute group/group?

Dear All:

For the compute group/group command, there is no instruction on how to get the interaction force (vector) between two groups. I can only get the energy (scalar) between the two groups with the follwoing commands:

compute 1 lower group/group upper
thermo_style custom step temp c_1

I appreciate your help on how to get interaction force between two groups using compute group/group command.

Thanks
Peter

The doc page explains that it also calculates
a vector of length 3 with the force, and refers
you to section 4.15 of the manual which
describes different things you can do with
"vectors" calculated with fixes, e.g.

thermo_style custom step temp c_1 c_1[1] c_1[2] c_1[3]

Steve

2010/12/27 peter pqx <[email protected]>: