[gmx-users] Add new residue to oplsaa force field

[Justin Lemkul]

On 12/17/14 4:41 PM, fatemeh ramezani wrote:
> Dear JustinHydroxyprolin dihedral coefficients there are not in ffbonded file in oplsaa forcefield. I need to find it, and I add.
> I have Hydroxyprolin charmm parameters (dihedral parameters). How can I convert charmm dihedral parameters to oplsaa parameters?Can you help me so that I resolve this problem?Thanks for your guides

You don't convert one force field to another.  Force fields are self-consistent 
entities.  You can't just port parameters over.  If OPLS-AA lacks suitable 
parameters for a dihedral, you have to parametrize it in accordance with that 
force field's methodology.  For OPLS-AA, this means doing dihedral scans with QM 
and tuning parameters to match the energy profile.  The procedure is well 
documented in the literature.

-Justin

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Justin A. Lemkul, Ph.D.
Ruth L. Kirschstein NRSA Postdoctoral Fellow

Department of Pharmaceutical Sciences
School of Pharmacy
Health Sciences Facility II, Room 629
University of Maryland, Baltimore
20 Penn St.
Baltimore, MD 21201

jalemkul at outerbanks.umaryland.edu | (410) 706-7441
http://mackerell.umaryland.edu/~jalemkul

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