Dear PhenixBB, I'm trying to refine a structure against potentially twinned data. I got the twin law from xtriage. phenix.refine starts, and at some point crashes with the messages below. Refinement proceeds to the end if I don't include twinning. Any suggestions? Thanks, Scott Traceback (most recent call last): File "/software/phenix-1.3b/phenix/phenix/command_line/refine.py", line 5, in <module> command_line.run(command_name="phenix.refine", args=sys.argv[1:]) File "/software/phenix-1.3b/phenix/phenix/refinement/command_line.py", line 81, in run call_back_after_monitor_collect=call_back_after_monitor_collect) File "/software/phenix-1.3b/phenix/phenix/refinement/driver.py", line 1325, in run log = log) File "/software/phenix-1.3b/phenix/phenix/refinement/strategies.py", line 559, in refinement_machine log = log) File "/software/phenix-1.3b/mmtbx/mmtbx/refinement/rigid_body.py", line 347, in __init__ fmodel_copy = fmodel.resolution_filter(d_min = res) File "/software/phenix-1.3b/mmtbx/mmtbx/twinning/twin_f_model.py", line 1042, in resolution_filter sf_and_grads_accuracy_params = dc.sfg_params File "/software/phenix-1.3b/mmtbx/mmtbx/twinning/twin_f_model.py", line 890, in __init__ u_part=self.scaling_parameters.u_part ) RuntimeError: cctbx Internal Error: /net/anaconda/scratch1/phenix/phenix-1.3b/cctbx/include/cctbx/xray/f_model.h(91): CCTBX_ASSERT((f_mask.size() == 0) || (hkl.size() == f_mask.size())) failure. -- _______________________________________ Dr Scott A. White Protein Crystallography Group School of Biosciences University of Birmingham B15 2TT E: [email protected] T: +44-(0)121-414-7534 F: +44-(0)121-414-5925 W: http://www.bip.bham.ac.uk/cryst ______________________________________