Hello CCP4 community, I'm posting at large regarding a previously raised issue for REFMAC for which I cannot find the conclusion in the old threads.
Specifically, does REFMAC add riding hydrogens during default refinement? Though I've not requested that any hydrogens be added, only used if in the input, I see the following in the output header: REMARK 3 HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS Does anyone know exactly what this remark is referring to? Are riding hydrogens added for stereochemical restraints, or are their scattering contributions calculated regardless of they are explicitly defined? Can the hydrogen behavior in REFMAC be more explicitly controlled. Thanks, --Paul
