Hi, Joakim- Hamiltonian exchange only should work if there is a lambda coupling parameter that defines the potential at each state. You need to define your pulling potential so that the coupling-lambda parameter can be used to define the different pulling location centers along your trajectory. Does this make it clearer?
On Thu, Mar 7, 2013 at 7:26 AM, Joakim Jämbeck <jamb...@me.com> wrote: > Dear gmx-users, > > I am currently trying to runt Hamiltonian replica exchange umbrella sampling > in hope to do some better sampling. > > I have generated a number of tpr-files along my reaction coordinate and they > all run fine in independent simulations. The issue comes when I would like > the replica exchange to start. > > The following line is used to initiate the exchange: > > mdrun_mpi -replex 1000 -s md -pf pullf -px pullx -multi 40 -maxh 0.5 > > All replicas have the same temperature and the following error is what I face > seconds after submitting the job: > > The properties of the 40 systems are all the same, there is nothing to > exchange > For more information and tips for troubleshooting, please check the GROMACS > website at http://www.gromacs.org/Documentation/Errors > > I could simply change the temperature between the replicas by 0.001 K and it > would run I think. But that is not very elegant. > > Does anyone have any suggestions? > > Thanks in advance! > > Best regards, > Joakim-- > 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 -- 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