[gmx-users] atomtype "OE" in charmm36

[Schirra, Simone]

Dear Gromacs users,

I want to simulate polyethylene glycol and I am using a script to build my .itp and .gro files. The script is designed to work with charmm35r, however I only found charmm36 available now (I read, that c35r was only temporary). I thought, it should work with this version as well.
When I try energy minimization, the atomtype OE is not found. OE is used for the ether oxygen's in the itp file.
I also found an ether toppar file at MacKerell Lab Hompage, however it seems to be designed for use with charmm rather than gromacs.
Is there a way to convert it for use with gromacs? Or is there another definition I can use to work with my PEG? Or maybe c35r is still somewhere around?

I would be very grateful if someone could help me!
Simone