Hi, Could the rupture suggest that perhaps the underlying QM/MM model is somewhat flawed?
What happens when you run the minimisation without the constraint between the QM and MM atoms? Do you have convergence problems? Gerrit Message: 2 Date: Fri, 2 Mar 2018 13:01:09 +0300 From: nikol...@spbau.ru To: gmx-us...@gromacs.org Subject: Re: [gmx-users] QM/MM optimization in gromacs/gaussian (nikol...@spbau.ru) Message-ID: <40fa81b002d9ded18e6f471f19a1ada7.squir...@mail.spbau.ru> Content-Type: text/plain;charset=UTF-8 And which one (and with what parameters) is better for the QM/MM optimization? Steep almost didn't change anything and I couldn't relax the system as I wanted. CG seemed to work fine, but in the end it teared an H-atom from my QM subsystem. BFGS could not work with the constraints which are necessary for the QM/MM calculations in gromacs... > > Hi, > > It is possible, but only using gromacs' internal optizers: SD(steep), CG, > or BFGS. > And you can only optimise minima, not transition states. > > Best, > Gerrit > > > > > > > > Message: 3 > Date: Thu, 1 Mar 2018 12:44:53 +0300 > From: nikol...@spbau.ru > To: gmx-us...@gromacs.org > Subject: [gmx-users] QM/MM optimization in gromacs/gaussian > Message-ID: <ff117f222d3d76fdce88a36282ae90b6.squir...@mail.spbau.ru> > Content-Type: text/plain;charset=UTF-8 > > Dear all! > > I need to perform the QM/MM optimization in the Gromacs/Gaussian > interface. However, I know that in 2015 this was not possible. > > The question: is there such an opportunity nowadays (I use gromacs 5.1.2) > and which kind of parameters I need to write in the .mdp file in order to > obtain such an optimization? > > Thank you in advance, > Dmitrii > > -- > 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. > -- 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.