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Hi Shane,<br>
<br>
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<div>I've got a question related to refinement of an ion on a
special position. I have a structure with an atom placed
squarely on the C2 axis. I've been able to get a
mostly-reasonable model by dropping in the ion at 0.5
occupancy and turning off repulsion for the ion in question,
as Pavel describes <a
href="http://www.phenix-online.org/pipermail/phenixbb/2018-February/023689.html"
moz-do-not-send="true">here</a>. It almost completely works.</div>
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<br>
OK, all sounds good so far!<br>
<br>
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<div>The thing I find now is that during refinement there can
still be some random drift of the atom away from the symmetry
axis, splitting from its symmetry ghost, while I know that it
should stay perfectly coincident. </div>
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<br>
Hm.. this is odd and I'm pretty sure the code that handles this
makes sure atoms on special position should stay there perfectly (no
drifting).<br>
<br>
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<div>My resolution is 3.1 and there's no indication of a
multiple conformation, so a split isn't justified. The most
parsimonious model should place the ion exactly on the C2. <br>
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<br>
All true!<br>
<br>
Looks like I need to investigate this in greater detail.. Would it
be possible to send me model and data files, as well as any ligand
cif (if used) and that will be a good start for me. I'm traveling
next week, so if I get files today I may be able to respond before
my travels.<br>
<br>
Pavel<br>
<br>
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