If by unstable refinement you mean a significant increase of Rfactors
during refinement, then there is a problem in the software you use and
the best thing you can do is to notify the developers of that software
so they can fix the problem.
I can't tell for other software, but I'm not aware of such thing
(unstable refinement) in phenix.refine. If you have a problem case I
would appreciate if you send it me so I fix the problem.
On 2/13/2009 6:36 AM, John Bruning wrote:
> I would like to survey the group for causes and potential solutions to
> unstable refinement (the steady and upward drift of R and Rfree in
> each cycle of refinement). I am currently aware of the following
> potential causes: twinning (meohedral, pseduomerohedral, or
> epitaxial), anisotropy, pseudosymmetry, the lack of appropriately
> tight geometric constraints, and extraordinarily high b-factors. If
> anyone has run into any other causes of unstable refinement, I would
> like to hear about them.
> John Bruning