Well - there will be a ripple, but is it there in the difference map as
well? that is meantto be less affected.
REFMAC5 claims to be able to refine some atoms anisotropically and
that would be a good place to start
Maybe you will need to read the documentation! There is some way of
requesting the option..
The PDB doesinclude structures with some anisotropic/ some isotropic B
values., usually waters
Eleanor
Klemens Wild wrote:
Dear friends of the Fourier transform,
I am refining a structure with 2 adjacent Hg atoms bound to cysteines
of different monomers in the crystal contacts, which means I need to
refine them as well. While the structure nicely refines (2.2 A data),
I do not get rid of negative density ripple layers next to them (-10
sigmas). My question: is this likely due to anistropy of the soft
mercury atoms (anisotropic B refinement decreases the ripples) or is
this likely a summation truncation effect prominent for heavy atoms?
Can I just anistropically refine the mercuries while I keep the rest
isotropic? Never saw this in a PDB. Suggestions are very welcome.
Greetings
Klemens Wild
