Hi, Could it be that the QM level of theory is not suited (candidates are charge and multiplicity) for the QM subsystem? What happens if you run a QM only calculation on your QM system ?
Gerrit Dear gmx users I'm doing an QM/MM simulation of a ligand-protein system by the Gromacs ORCA interface. When I set constraint = none in the Gromacs mdp file the bonds' length of the atoms oscillate extremely even those that did not index as the QM atoms e.g. aromatic rings will be twisted during the mdrun and when I set constraint = all-bonds I get this error ?Step 1, time 0.002 (ps) LINCS WARNING relative constraint deviation after LINCS? I thinks this happens because I constrained the reactant atoms explicitly in the topology file. Are these kind of oscillations usual in QM/MM simulations? Note When I set QMMM = No in the mdp file no unusual vibration happens. Any help will be appreciated. Sincerely M.Javaheri Could it be that the level of QM theory is not ------------------------------ -- 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. End of gromacs.org_gmx-users Digest, Vol 160, Issue 128 ******************************************************* -- 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.
