On Mon, Feb 18, 2013 at 12:10 PM, Mark Abraham <mark.j.abra...@gmail.com> wrote: > b) a particle needs to be at that immobile reference point - you can > measure a distance to a point whether or not there is something there.
I'm not sure that it's the same use-case... I recently talked to someone trying to define such a fixed particle to be used as a pull group. This pull group could then be set as reference in the middle of the PBC box, such that the pull distances are smaller than half the box size. The fact that the particle is really fixed when the PBC box is allowed to change dimensions is not a big problem, if needed the size of the box for each trajectory frame can then be used to correct distances. I don't know what was the outcome, but I'm curious to see such a setup. Cheers, Bogdan -- gmx-users mailing list gmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
