[gmx-users] Going from OPLS-AA dihedrals to CHARMM22 dihedrals.
jalemkul at vt.edu
Wed Jul 16 02:36:05 CEST 2014
On 7/15/14, 1:29 PM, Dawid das wrote:
> Dear Gromacs experts,
> I have following issue. I need torsional parameters from this publication:
> D. V. Dmitrienko et al., Biochemistry (Moscow), 2006, Vol. 71, No. 10,
> where OPLS-AA FF has been used but I need to adapt them for CHARMM22 FF.
> Now the thing is that there are two different torsional energy expression
> used in those FFs.
> How can I go from one to another?
> To be precise I want to adapt parameters from the above mentioned
> publication to expression for torsional potential from this publication:
> N. Reuter et al., J. Phys. Chem. B, 2002, Vol. 106, 6310-6321
> Any help will be appreciated.
It's not wise to try to hack parameters developed for one force field into
another. Dihedrals are especially dangerous, because their validity is also
dependent upon the nonbonded interactions of atoms 1 and 4 in the interaction;
differences in charges and LJ parameters between OPLS-AA and CHARMM will make
the dihedral non-transferable.
Justin A. Lemkul, Ph.D.
Ruth L. Kirschstein NRSA Postdoctoral Fellow
Department of Pharmaceutical Sciences
School of Pharmacy
Health Sciences Facility II, Room 601
University of Maryland, Baltimore
20 Penn St.
Baltimore, MD 21201
jalemkul at outerbanks.umaryland.edu | (410) 706-7441
More information about the gromacs.org_gmx-users