The cell predictions look like they're overlapping but the spots are not. At first glance it looks like the unit cell is incorrect and is too large.
You seem to have intense spots mixed in with weak spots at the same resolution. Smells like multiple unit cells / cracked crystal (which if close together would confuse the autoindex into thinking it's a larger unit cell. . Difficult to tell without seeing the images.
The data/spots (not the predicted spots) show reasonable separation.
How does the unit cell of the derivative compare with the native?
F
On Jul 16, 2012, at 2:52 PM, Jason Busby wrote:
> Hi,
>
> I have a crystal with a large unit cell in P21221 (a=134 b=151 c=276) and I'm wondering if I have a problem with overlaps. I have a native dataset, and am trying to get phases. I've collected a Pt soak data set on our home source with a 0.5˚ oscillation angle, but the anomalous signal drops off after about 8Å. I am wondering if this is a problem due to overlaps at higher resolution.
>
> The Pt dataset has been integrated with XDS, and there don't seem to be too many rejects, but looking at FRAME.CBF it looks like the predicted spots are overlapping at higher resolution. You can see a zoomed-in part of FRAME.CBF here:
> http://imgur.com/1WShV
>
> Should I be concerned with this? The crystal mosaicity from XDS is 0.25, so fairly low. What can I do about this, should I try smaller oscillation angles?
>
> Thanks,
>
> Jason.
>
> --
> Jason Busby
> PhD Student
> Laboratory of Structural Biology
> School of Biological Sciences
> University of Auckland
> Thomas Building 110
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>
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Francis E. Reyes PhD
215 UCB
University of Colorado at Boulder
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