Dear GROMACS Community, First of all, if someone got this email twice, I am sorry. It is my first post and I was not sure if it worked.
I am trying to do a simulation using a tabulated potential which forces me to use the group cut-off. I get a drift in the conserved quantity of -600KJ/mol/ns. My system consists of 1000 rigid TIP4P water molecules and a Na+ ion. I imagine that eventhough it will soon be deprecated the group cutoff scheme still works correctly. I have tryed to change the parameters without success and in any case the ones I use seem reasonable (in my experience using other programs). The rdfs of the system look normal so I ruled out topology problems. It seems that the problem is in the group cut-off since when I change the tabulated potential for a regular vdw the problem persists. I have followed the instructions of: http://www.gromacs.org/@api/deki/files/94/=gromacs_nb.pdf to implement the tabulated potentials. Is this the kind of energy drift acceptable? I have pasted a copy .mdp Thanks for your help, Sergio Perez-Conesa integrator = md dt = 0.001 nsteps = 100000 init-step = 0 cutoff-scheme = group nst-list = 1 verlet-buffer-tolerance = 0.0005 ns-type = grid rlist = 1.3 pbc = xyz coulombtype = PME-switch rcoulomb = 1. rcoulomb-switch = 0.95 pme-order = 4 fourierspacing = 0.1 ewald-rtol = 1.e-5 vdwtype = user rvdw = 1.0 DispCorr = No tcoupl = v-rescale tc-grps = System ;nsttcouple = 1 tau-t = ref-t = 300.0 constraints = all-angles constraint-algorithm = LINCS lincs_iter = 1 lincs_order = 4 energygrps = NA OW energygrp_table = NA OW comm-mode = linear -- 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.