Hi, I am having a problem with hydrogens causing steric clashes after refinement. I added hydrogens to my pdb using: "phenix.ready_set model.pdb". I was given two sets of coordinates (my model and a pdb for Iron atoms) I included this new model in the next round of refinement but I did not include the pdb for the Iron atoms. I ran refinement with the folowing parmeter file: refinement.main.ordered_solvent = true #refinement.main.ordered_solvent.mode=filter_only refinement.refine.strategy = individual_sites+individual_adp #refinement.refine.adp.individual.isotropic = "chain W" refinement.output.prefix = CIN4_refine refinement.output.serial = 18 refinement.output.write_def_file = True resolution is 1.37A with close to 400,000 unique observations (obs/param is still about 4) Stats: Rwork Rfree bonds angles start: .1444 .1723 .016 1.617 end: .1371 .1657 .010 1.301 I also ran wxu and wxc optimization from the command line. I know that the defualt is "riding-model" so that the hydrogen atoms are not refined. However, I thought that the program would be able to avoid steric clashes. Is there an aditional command I need to turn on to account for this? I am currently fixing every hydrogen that clashes on an individual basis in coot. There are also a handfull of hydrogens that exist out in space that I decided to delete. Thank you very much for your help. -Yarrow