[gmx-users] Unknown bond_atomtype when trying to use charm27 with cgenff

[Jonathan Phillips]

>FWIW, we have a complete CHARMM36 + latest CGenFF available at our website to save you some pain: http://mackerell.umaryland.edu/charmm_ff.shtml#gromacs

That looks helpful.  Thanks.

>So if it finds a bonded interaction that involves an atom type
>it doesn't know about (e.g. you have a type in ffbonded.itp but not
>ffnonbonded.itp, which I bet is the case here) you get a fatal error.

Got it!  It's a little more subtle that that though.

forcefield.itp has
>#include "ffcgenbonded.itp"
>#include "ffcgennonbonded.itp"
so it's loading the bonded parameters before the non-bonded, it needs
to be the other way around.  I'd never have worked that out on my own.

Now to fix the next error.


Thanks for the help!

Jon