[gmx-users] New force fields

[Ram'on Garc'ia Fern'andez]

On Thu, May 02, 2002 at 11:58:04AM -0700, Erik Lindahl wrote:
> Are there other features used by some force fields? Some ancient 
> versions of AMBER used to need 10-12 interactions, but I don't think 
> anybody is using it now...
> 

Although not needed for supporting other force-fields, one feature that
I find  essential is the capability of using different potentials for
different atom types. At present all the atom types must use the same
potential, albeit with different parameters.

In addition, the procedure for adding a custom potential (that is, with
a different formula) should be documented (as opposed to adding a potential
defined by a table, that is well documented). More that two parameters
should be allowed.

This is necessary for generating startup configurations of polymer melts.
In that case, I use a soft potential. This soft potential is different for
different pairs of atom types.

Ramon