[gmx-users] force constants
feenstra at few.vu.nl
Tue Nov 30 17:18:46 CET 2004
> I am wondering how force constants are derived for various FF in
> GROMACS. I want to get the force constant for Fe=O bond. I tested C=O
> force constant for Fe=O in my model and it worked well. Now I want to
> supply Fe=O bond parameters for FF, which are right for that model.
They are normally irrelevant, since bonds are constraint to a fixed length.
I would be surprised if anybody in the last years actually spent time
optimizing them in the Gromos forcefields.
Probably, they derive directly from (very) early forcefields, and would
indeed mostly be based on IR frequencies. I don't think they were ever
optimized to any extent to tune MD results.
| | |
| _ _ ___,| K. Anton Feenstra |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
|( | )| | | De Boelelaan 1083 - 1081 HV Amsterdam - Netherlands |
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