I have an issue with heme minimization, Fe atom leaves a heme plane. I saw at least one user had the same issue and got help to solve it (
https://www.cgl.ucsf.edu/pipermail/chimera-users/2019-July/015972.html). I could try the protocol described there, but I don't have the heme.defattr file. I hope you can help me with it too. I have attached a pdb file with this issue.