[gmx-users] ions.itp => no BR- ion defined (FF_Gromos 96)

Chih-Ying Lin chihying2008 at gmail.com
Wed Nov 5 18:30:09 CET 2008

There is no BR- ion defined in ions.itp.
Justin suggested "Proper parameterization is an extensive procedure".

As I checked the FFG53a6nb.itp, there are many sets of parameters
between atoms. I might get the sets of force field parameters for Br-
, something as described by FFG53a6nb.itp.

How to do "Proper parameterization" with a more understandable method?

If the solution is very dilute, Br - ions will have very limited power
affecting the whole system, I suppose. Are there any alternative ways
to solve the problem ?

Thank you

Chih-Ying Lin wrote:
> Hi
> In the ions.itp, there is no BR- ion defined  (FF_Gromos 96).
> But, it was defined in FF_OPLS.
> How did people solve the problem?
> Could I simply use all of  BR-atom (assign it a -1 charge) non-bonded
> parameters in FF_Gromos96 instead?

No.  Assigning parameters is far more complicated that picking and choosing and
putting them in whatever force field you wish you use.  Proper parameterization
is an extensive procedure.


> Thank you
> Lin
> _________________

More information about the gromacs.org_gmx-users mailing list