Hello all, I am trying calculate desolvation free energy of Na+ in water using option couple-moltype, not by creating B-topology in the .top file.
At first, I switched off coulombic interaction using: couple-moltype = Na+ couple-lambda0 = vdw-q couple-lambda1 = vdw Then I tried to switch off LJ interaction using couple-lambda0 = vdw and couple-lambda1 = none, but obtained this warning: WARNING 1 [file equil_NVT000.mdp, line 95]: For proper sampling of the (nearly) decoupled state, stochastic dynamics should be used This is strange, because my .mdp file has only 94 lines. Thanks in advance for any help or suggestion. Best, Eva For convenience, I am pasting weak coupling algorithm section and free energy section from my .mdp file. The simulation was performed at constant volume using strong temperature coupling, since it was an equilibration run. ; OPTIONS FOR WEAK COUPLING ALGORITHMS Tcoupl = v-rescale tc-grps = system tau_t = 0.1 ref_t = 300 nsttcouple = 1 ; Free energy control stuff free_energy = yes init_lambda = 0.0 delta_lambda = 0 foreign_lambda = 0.1 sc-alpha = 0.7 sc-power = 1 sc-sigma = 0.3 nstdhdl = 10 separate-dhdl-file = yes dhdl-derivatives = yes dh_hist_size = 0 dh_hist_spacing = 0.1 couple-moltype = Na+ couple-lambda0 = vdw couple-lambda1 = none couple-intramol = no -- 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
