Hi Miguel,
there are limits and they are applied to total B-factor:
- minimal Biso should be positive;
- anisotropic ADP matrix is always enforced to be positive definite.
Pavel.
Thanks, it is clear now.
I have a last concern, though. Does phenix impose minimal values to
the refined ADPs? I guess it does not, for I have found nothing like
that in the documentation. But, if it does so, are they imposed to the
individual B-factors or the B-overall is also taken into account? In
the former case you might have problems with the refinement in a case
as the one I described in my previous e-mail (coming from a model with
artificially low, 'residual' B-factors).
