Dear all, I have a protein-DNA structure that has six molecules in ASU. All six molecules share the same sequence and very similar structure. However, only three of them bind to DNA and conformations are slightly different from the other three. By default, PHENIX will consider six molecules into the same NCS group. Now I am trying to set up two NCS group, e.g. chain A,B,C are in one group (no-DNA), chain D, E, F are in another group (DNA-bound). So I did the following steps: 1. I used PHENIX GUI and go to 'Utilities' -> 'Detect NCS Groups'. 2. Put chain A, B, C in 'Torsion NCS restraint group 1'. 3. 'Add group' and put chain D, E, F in 'Torsion NCS restraint group 2'. 4. Click 'Update and exit'. However, after that, when I re-open 'Utilities' -> 'Detect NCS Groups', I found all six chains A-F are in group 1, and all six chains A-F in group 2. Did I do something incorrectly? Or any other suggestion for my purpose? Thank you! Best, Xiao