Experimental Data Question
![](https://secure.gravatar.com/avatar/f3de86147d439720e7eb4802800a75be.jpg?s=120&d=mm&r=g)
It looks like phase_and_build only takes reflections input as F SIGF. I had to use a reflection converter as I had a .sca file with I SIGI data. -- Yuri Pompeu
![](https://secure.gravatar.com/avatar/cad35f4dd77b3ab8e60ede4e3d54c6f4.jpg?s=120&d=mm&r=g)
On Sat, Jul 16, 2011 at 9:00 AM, Yuri
It looks like phase_and_build only takes reflections input as F SIGF. I had to use a reflection converter as I had a .sca file with I SIGI data.
Okay, this probably means that the reflection file converter added new R-free flags - or if not, phase_and_build certainly would have. As a result, you've run a refinement with one set of flags, then rebuilding (which includes more refinement) with another set of flags. I'd recommend starting back with phase_and_build again, using the model from the first refinement, but this time with the "_data.mtz" file that came with it for your reflections. Then use those reflections with all subsequent refinements. (This isn't always necessary - if your refinement still has a way to go, one round with simulated annealing can help de-bias R-free - but it's the most conservative approach. If you decide to continue with the existing model, however, use the R-free flags that phase_and_build used - either reflections.mtz if it has them, or exptl_fobs...mtz [making sure *not* to use the "experimental" phases it contains].) -Nat
participants (2)
-
Nathaniel Echols
-
Yuri