Hi Espresso-verse,
I know there are a few threads of this nature
already in the archives, but I have a clarifying question about the
tabulated angle potential.
I am building a coarse grained polymer from tabulated potentials calculated by
probability densities. The backbone is composed of beads of type B and
each B bead has one pendant group of type A. Therefore, I have nonbonded
potentials, AB and BB bonded potentials, and BBB and ABB angular bond
potentials.
The UG states that the force must be scaled with the
inverse length of the connecting vectors. For the angular bond potentials, do I need a 3 dimensional map
of V(r,phi) in order to calculate this? Right now I only have V(r) and
V(phi)
The part that confuses me is that if one builds the tabulated file like this
#N_points 0 3.14159
phi (-dV/dphi)/r V(phi)
....
....
Then the r to use is not obvious to me.