Charmm36 does not recognize CU atom

Hi all,
I am going to use Charmm36 2020 to prepare human superoxide dismutase 3 (PDB ID 2JLP). However, the force field does not recognize CU atom.
How this problem can be fixed?


the atomtype CU is defined in CHARMM36 port for GROMACS. Probably the issue is different. Where did you get the error and what error do you get?

CHARMM supports elemental copper (via an auxiliary parameter set) but does not officially support Cu2+. There are parameters available from that could be used, but these have never been formally evaluated for compatibility with the protein force field.

thanks for your reply. I have got the error following pdb2gmx command. the error just says that CU atom is unknow.

Thank you very much for your response. Now I have the same problem with ZN atom.