[gmx-users] coulomb energies

[David]

On Fri, 2005-04-22 at 08:51 -0700, Edgar Luttmann wrote:
> Hi,
> 
> if I set the coulombtype to user and supply a table.xvg, which contains only 
> zeros, I would have expected to turn off the coulomb interactions.
> 
> But the coulomb-SR stays at some small value -27 or -48 (version 3.1.4 and 
> 3.2.1 respectively) as the value is on the order of -11000 if I use the 
> cut-off. Furthermore I get several LINCS Warning upon turning off the coulomb 
> interaction.
> 
> Any suggestions where this coulomb energy and the "instability" comes from?
Please find out where the coulomb energy comes from.

Instability comes from the fact that your force field is now unbalanced,
you only have Van der Waals interactions. Try it for a box of water...

> 
> Cheers
> Edgar
> 
> --
> Edgar Luttmann
> 
> Stanford University, Stanford, CA, USA
> Folding at home - distributed computing
> _______________________________________________
> 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, Assoc. 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
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++