[lammps-users] OPLS LAMMPS


which OPLS parameter file should one use with LAMMPS? The one suggested by
NAMD from http://brooks.scripps.edu/charmm_docs/charmm.htm doesn't use the
fourier formula for the dihedral but the charmm formula. The one from e.g.
Gromacs I don't know how to convert.

Roland Schulz

I'm not familiar with OPLS details. But for LAMMPS, you need
to list pair, bond, angle, etc coeffs directly in the input script or
data file. So you can't use any OPLS file directly. Rather you
need to find the OPLS formulas you want that are in LAMMPS (see
the doc pages), then extract the coeffs for those formulas from
your OPLS parameter file.

There are some tools that automate this for CHARMM, AMBER,
Compass force fields (see lammps/tools), but no one has done
that for OPLS so far as I know.