[gmx-users] CHARMM force field implementation in Gromacs : conversion of periodic into Ryckaert-Bellemans parameters.

[Nicolas SAPAY]

Hello,

I have noticed that both in the Yuguang Mu's and the Mark Abraham's work,
the periodic parameters of dihedral angles have been converted into
Ryckaert-Bellemans ones. I have tried to find more info about this in the
CHARMM and Gromacs documentations but I have not found much. Why exactly
this conversion should be done since the periodic potential is implemented
in both force fields? My problem is that several dihedral angles cannot be
easily converted in RB parameters since their multiplicities is equal to 6
and the RB potential implemetation is limited to 5 constants.

Thanks

Nicolas

-- 
[ Nicolas Sapay Ph.D. ]
University of Calgary, Dept. of Biological Sciences
2500 University Dr. NW, Calgary AB, T2N 1N4, Canada
Tel: (403) 220-6869
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