I am using the CustomTorsionForce with the potential: "0.5*k*(1-cos(theta-theta0))" where theta is the current dihedral angle and theta0 is the equilibrium dihedral angle. I would like to compute the force of this potential with respect to theta therefore I need the current theta. Is there a way to ...

Thank you so much, I managed to get OpenMM to report the energy decomposition and it matches the energy decomposition reported by NAMD! But I still cannot figure out why I am getting a lot more dihedral angles in OpenMM compared to what is reported by NAMD and in the PSF file (the dihedral section r...

I have been trying to do energy decomposition of a system running CHARMM36 FF on OpenMM. I am using scripts provided by CHARMM-GUI to run the simulation because they have implemented CustomNonBondedForce to do force-based switching. After creating the system and adding in the coordinates I ran the f...