I know CHARMM FF uses Lorentz-Berthelot rules but is it possible to use custom epsilon and Rmin/2 for cross terms?
For example in Gromacs and Lammps, it is possible to define values in a format like CT1 OT1 0.24 0.06, when these values are present, they will be used instead of the combination rule that you specified and when they're missing the combination rule will be used.
Does CHARMM have such settings or am I only allow to use Lorentz-Berthelot?
I imagined info about this would be in the nonbonded documentation but I didn't find anything useful.
Thanks in advance!