[lammps-users] What is the force magnitude of Planar Indenter in Fix Indent command

Dear All,

I am wondering whether the equation in manual:

F® = - k (r - R)^2

is still available for plane indenter. If not? What is the equation/
If yes, what is the meaning of “R”.

Many thanks.

Is it reduced to


I feel strange about this equation: does is mean the larger the distance of some atom from the indenter, the bigger the force?

I have one more question here, why the sign is “minus”? While in some literature it is “plus” sign.

If it's in the manual, it's in the code. R is the distance
of the atom from the plane.


The negative sign is b/c atoms only feel a force when
they are inside the indenter. The further they are inside,
the bigger the force.