[gmx-users] Backward (CG to atomistic), no charmm27

[shivangi nangia]

Hello,

I was able to convert my coarse grained system to all-atom using the
backward script.
However, it (Mapping folder) only had option for charmm36.

I have an all-atom .gro file and .top file for charmm36 but I need t run my
simulations with charmm27.

Doing pdb2gmx with all-tom .gro file runs into error which I believe is for
mismatch in atom types between charmm36 and 27.

Also,on using the command (./initram.sh -f system.gro -f system_aa.top -po
backmapped.top -from martini -to charmm27)  handled the protein part of the
system but ran into error for POPC, but changing -from martini -to charmm36
 successfully converted to all atom.

Please suggest.

Thanks,
sxn