On Tue, Oct 10, 2017 at 5:42 AM, Faezeh Pousaneh <fpoosa...@gmail.com> wrote:
> Hi Mark > > I have a given function for pseudo hard-sphere potential, which has > different powers than LJ and a constant. I have to insert the constant in > order to properly define the cut-off for my hard spheres. > I just realized that I can use "user-specified potential". I guess I can > include the constant there, yes? > > One more thing, I need to have my own particles, spheres with a diameter > "a". How can I have them in gromacs? > . > This should get you started in generating your own tables: http://www.gromacs.org/Documentation/How-tos/Tabulated_Potentials If all you're looking to do is create repulsive spheres (again, not true hard spheres as Mark said; just removing attractions from the interactions), then cut off your interactions at 2^(1/6)*sigma and shift the potential at the cutoff to zero in your table. If you want different size spheres you need to subtract an additional term from r in the denominators of the c6 and c12 terms. -- James "Wes" Barnett Postdoctoral Research Scientist Department of Chemical Engineering Kumar Research Group <http://www.columbia.edu/cu/kumargroup/> Columbia University w.barn...@columbia.edu http://wbarnett.us -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.