Run phenix.fmodel to calculate structure factor of 3ONS (Solvent is ignored). Write a python code to calculate structure factor and make sure we get the same result. The python code will have two versions (the two versions should give the same result):
. Perform symmetry operators to build a complete unitcell, and then calculate SF by assuming no mirror molecules
. Do not expand the symmetry. Calculate SF under proper symmetry operators (use Seitz matrices as Phenix does)