Hi George, It’s true that ensemble refinement in phenix.refine is not available for twin data. This is because the way it was originally implemented (mostly by Tom Burnley, quite a while ago) is heavily tied to the maximum-likelihood refinement target function. In the case of twinning, we use an LSQ target, and enabling ensemble refinement in this context would require rewriting a significant portion of the code. I looked into this shortly after we spoke about it at the SB Summit at Arrowhead Lodge, at first hoping I can fix this quickly, but I gave up after a day of poking around the code. Bottom line — it’s possible to implement, but it would require about a week or two of full-time, undistracted effort. All the best, Pavel On 9/24/25 14:21, [email protected] wrote:

Last version of phenix I checked, one cannot do an ensemble refinement with twin data. Anyone know how to do this? If its not worth fixing, can anyone point to a sample cctbx script to start from? Thanks, _______________________________________________ phenixbb mailing list -- [email protected] To unsubscribe send an email to [email protected] Unsubscribe: phenixbb-leave@%(host_name)s