[gmx-users] tpbconv -zeroq results all coulombic energies to zero

[David van der Spoel]

On 2010-12-03 08.45, BIN ZHANG wrote:
> Hi, all:
>
> I was trying to use "tpbconv" to modify the tpr file with the command:
> tpbconv -s %s.tpr -nsteps -1 -zeroq -n index -o final.tpr
>
> It basically sets the charge of one group to zero. However, when I
> perform mdrun -rerun, all the coulombic energies are zeros, i.e.,
> Coulomb-(SR), Coul.-recip. This really does not make sense since I still
> have atoms in other groups that are charged. I was using gromacs4.0.7.
>
Please check using gmxdump that there still are charged groups left in 
your tpr file.

> Has anyone seen this before? What exactly is the correct way to zeroize
> the charge for a group of atoms?
>
> Thanks,
> Bin
>


-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205.
spoel at xray.bmc.uu.se    http://folding.bmc.uu.se