[gmx-users] PME and atom-based cutoffs

[David]

On Wed, 2003-12-10 at 02:12, Malcolm Gillies wrote:
> Are atom-based cutoffs (rather than group based) used automatically when
> coulombtype = PME ?
No! We still use charge groups with PME, mainly for efficiency of
neighborsearching. It does not make a difference in energy and forces,
though.
> 
> I want to make sure that I can dispense with defining proper charge
> groups for my custom residue types, if I only plan to use PME.
> 
That shouldn't be a problem indeed, just make them not too big (3-4
atoms). The charge groups also influence the Van der Waals forces in the
same manner, but if your cut-off is "large enough"(TM) that shouldn't be
a problem either.


> cheers,
> 
> Malcolm
> --
> Malcolm Gillies <Malcolm.B.Gillies at anu.edu.au>
> Postdoctoral Fellow, Computational Proteomics and Therapy Design Group,
> John Curtin School of Medical Research, Australian National University
> 
> _______________________________________________
> gmx-users mailing list
> gmx-users at gromacs.org
> http://www.gromacs.org/mailman/listinfo/gmx-users
> Please don't post (un)subscribe requests to the list. Use the 
> www interface or send it to gmx-users-request at gromacs.org.
-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assist. Prof., Molecular Biophysics group,
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://xray.bmc.uu.se/~spoel
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++