I am going to try to guess in this one.
As you say, the positions of the iodines cannot be challenged. But maybe
their occupancies can. Is there anomalous signal from iodine at your
wavelenght? Are you expecting radiation damage? In any case:
I see a spherical shell of low density around each one
Hello,
the guess about ripples is most likely correct. Just do this simple
experiment: place one iodine in a middle of a cubic box and compute
F-calc map. You will see mazing picture! At least I enjoyed. You
will see a number of concentric shells of density around iodine,
positive and
