Hello. When I use addH to add H atoms on N atom in N-terminal of Peptide chain, I find 3 H were added on this N. Why the addH result is C-NH3 and not C-NH2? Thanks! -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://plato.cgl.ucsf.edu/pipermail/chimera-users/attachments/20210616/251bd552/attachment.html>