Dear ChimeraX staff, 

For some mmCIFs, ChimeraX displays bonds that are physically unrealistic. For example, if you take PDB 9S2E ChimeraX draws a bond between residue /IN:52 and and /IN:154 (see screenshot).  The PDB mol viewer (https://www.rcsb.org/3d-view/9S2E) does not display this bond. 

I noticed that structures in PDB format don’t show these bonds, so this is probably due to some connectivity records in cif format. I also have only observed this in nucleic acids, not proteins.

Is this a bug that could be addressed?

Thanks a lot and best wishes,

Matthias