Hi Dmitry, if your model is composed of chains related by some rotation/translation (does not matter what symmetry), you can ask Phenix real-space refinement to identify and use that symmetry as "NCS" constraints (yes, NCS is a legacy term from Xtallography!). Aprart from this there isn't anything particular.. Alternatively, you can manually specify the master and symmetry related chains when setting up refinement job. Pavel On 2/1/24 02:48, Dmitry Semchonok wrote:

Dear colleagues,

Is there any specific procedure for Real space refinement in Phenix, having a map and model when working with helical structure?

Many thanks

Kind regard, Dmitry