It looks like you are using the EAM potential. According to the doc page for compute group/group, (http://lammps.sandia.gov/doc/compute_group_group.html):

Not all pair styles can be evaluated in a pairwise mode as required by this compute. For example, 3-body and other many-body potentials, such as Tersoff and Stillinger-Weber cannot be used. EAM potentials only include the pair potential portion of the EAM interaction when used by this compute, not the embedding term.

I would check that first.

Stan

Dear Stan,

I used LJ potential between the indenter and substrate. And I just compute the force between them, so I think the command “compute group/group” only compute the force which is caused by the LJ potential.

If I misunderstand, could you please explain it ?

Thank you,

Nghia

Vào ngày 1:45 Thứ Ba, 7 tháng 1 2014, Stan Moore [email protected] đã viết:

It looks like you are using the EAM potential. According to the doc page for compute group/group, (http://lammps.sandia.gov/doc/compute_group_group.html):

Not all pair styles can be evaluated in a pairwise mode as required by this compute. For example, 3-body and other many-body potentials, such as Tersoff and Stillinger-Weber cannot be used. EAM potentials only include the pair potential portion of the EAM interaction when used by this compute, not the embedding term.

I would check that first.

Stan