If you want a solid system, where atoms are arranged as in FCC, this is another talk.
There two way to achieve your goal. Either -- 1) you write a simple program which places argon atoms as in FCC. OR 2) you try to freeze my system into your system using simulated annealing implemented in gromacs. Provided that argon is a pretty simple system, this should not take too much time. At least, I can say that our students get it (216 atoms) freezed during one laboratory work. BTW, there is no guarantee that the freezing point of the classical argon model is perfectly reproduced. My guess is based on the fact that the density of the liquid phase (in the NPT ensemble) is not ideal. Dr. Vitaly V. Chaban, 430 Hutchison Hall Dept. Chemistry, University of Rochester 120 Trustee Road, Rochester, NY 14627-0216 THE UNITED STATES OF AMERICA On Fri, May 25, 2012 at 10:44 AM, ahmed sta <ahmedsta6...@yahoo.fr> wrote: > Sorry. My aim is to model FCC Argon (not liquid state) and i am trying to > define that geometry > Can you help me please? > > Regards > > ________________________________ > De : Dr. Vitaly V. Chaban <vvcha...@gmail.com> > À : ahmed sta <ahmedsta6...@yahoo.fr> > Cc : gmx-users@gromacs.org > Envoyé le : Vendredi 25 mai 2012 17h36 > Objet : Re: Gromacs > > Dear Ahmed - > > I do not understand how you imagine "FCC geometry" in the liquid state > of matter. > > If you want to just resize my system, use the standard "genbox" > utility and then re-equilibrate at the desired temperature and density > (if you want to fix density, of course). > > > Dr. Vitaly V. Chaban, 430 Hutchison Hall > Dept. Chemistry, University of Rochester > 120 Trustee Road, Rochester, NY 14627-0216 > THE UNITED STATES OF AMERICA > > > > On Fri, May 25, 2012 at 10:30 AM, ahmed sta <ahmedsta6...@yahoo.fr> wrote: >> Dear Vitaly >> >> >> I am an engineer student and i am now trying to use Gromacs >> I found your Argon molecule defined topology created in May 2009 >> I want to ask you how to define my own geometry on Gromacs >> In fact i am trying to define liquid Argon system with a density >> equilibrated at 90K. My system should have a FCC geometry and containing >> for >> example 500 atoms >> >> >> I really need your help >> >> Best regards >> >> >> >> >> Ahmed Sta >> Ensta Paristech engineering school >> ahmedsta6...@yahoo.fr > > -- 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
