SwissParam provides topology and parameters for small organic molecules compatible with the CHARMM all atoms force field.
Created and maintained by the Molecular modeling group, SIB.

When using the MMFF-based approach, the data are derived from the Merck Molecular ForceField (MMFF). Dihedral angle terms as taken as is, while only the harmonic part of the bond, angle and improper terms are retained. Charges are taken from MMFF. Van der Waals parameters are taken from the closest atom type in CHARMM36.
When using the multipurpose atom-typer for CHARMM (MATCH) approach, the data are derived from CHARMM General ForceField. Atom-types are assigned by a general chemical pattern-matching engine. Charges and force field parameters are assigned compared to a list of chemical fragments.
These parameters are intended for "drug design" type calculations, like docking, minimizations, rapid binding energy estimation (LIECE), etc...
Deeper parameterizations are required for applications in which a very fine description of the molecule is required, (e.g. normal mode calculations...).

SwissParam results can then be used as a starting point for such a procedure.


SwissParam is provided free-of-charge in the hope that it will be useful.

The SIB will not look queries from users, nor share them with a third party.
However, we make no guarantees about data confidentiality on this public service website.

We make no representation or warranty regarding results obtained from using any information provided through this server.

We bear no responsibility for any incidental or consequential damages or direct or indirect damages that result from the use of results, data or information, which have been provided through this server.