Hi,
From my rather limited experience ...
Is your EXAFS data collected on a crystal or in solution? If the latter, it is worth remembering that the chemical environment in solution and in crystal can be different. Moreover, atomic coordinates and bond distances determined via crystallography are associated with some errors. And if the As is not fully occupied in your crystal structure, your crystal structure is likely to be an average of the As-bound and As-free states. Maybe you can first check if the bond distances agree with each other within experimental error, then decide whether it is really worth contstraining the coordinate bond distance. Hope that helps, Geoffrey Kong
Hello I would like to constrain an As-S bond distance to fit known EXAFS data. I tried to do this by adding a LINK card with the distance to the header of the PDB and turning LINK to Y, but this is not working. The bond distances after refinement in Refmac 5 are longer than expected. How can I fix this problem? Thanks Debbie
