[gmx-users] Ewald summation: segmentation fault!

[Vincent Ballenegger]

Bert de Groot wrote:

>I'd be surprised if your system would run. You have opposite charges
>and no vdw parameters, ie the particles can approach each other to
>zero distance very rapidly, causing the electrostatic energy (and forces)
>to explode. Strange that you don't run into this problem with PME or PPPM
>though...
>
Sorry, I forgot to say that I keep the 2 ions fixed in space by setting
their velocity to zero at every time step. The same problem of segmentation
fault occurs in the original version of gromacs, in which case I use the
freeze option:

freezegrps               = Na+ Cl-
freezedim                = Y Y Y Y Y Y

Vincent