[gmx-users] COMPASS force field revisited Bond Dihedral and Angle Dihedral cross terms

[David van der Spoel]

On 2/21/12 6:17 PM, Richard Broadbent wrote:
> Dear All,
>
> I am considering conducting a simulation of a polymeric system in
> gromacs. I would like to use the COMPASS forcefield as it has a complete
> parameter set for my molecule.
>
> I believe the majority of the implementation is simple (though long and
> fiddly). However, it has Bond-Dihedral and Angle-Dihedral cross terms.
> These terms are not listed in either Chapter 4 or 5 of the Manual. Which
> leads me to believe that they are not implemented. However CMAP
> dihedrals are not documented in chapters 4&  5 and they are implemented
> in the code. I therefore had a quick look in src/gmxlib/ifunc.c and
> couldn't see those terms. However, my knowledge of the layout of the
> source code is extremely limited so I could be looking in the wrong
> place, and thought it best to ask.
>
> Are Bond-Dihedral and Angle-Dihedral cross terms available in gromacs
> 4.5.5?

What do the functions look like?

Most likely they are not implemented though if they're not in the manual.

>
>
> Thanks,
>
> Richard
>


-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Professor of Biology
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://folding.bmc.uu.se
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