I am trying to minimize the crystal structure of a protein using Chimera. But the program could not minimize the water molecules of the protein. I added hydrogen atoms to the whole structure. But during the minimization, it is showing the following error:

No MMTK name for atom "H" in standard residue "HOH"

It would be very helpful for me if you can suggest what changes I should make.

Thank you!

Sincerely

Gourav Das

Research Scholar

Department of Chemistry

IIT Kharagpur

India