Is it possible that your crystal is not really a single crystal, or has
multiple domains? I had a similar problem with an otherwise beautifully
diffracting crystal (beyond 2.0 A) whose integration rapidly broke down
after a few frames. On close inspection, it was possible to visualize
multiple lattices in the diffraction images. At some rotation angles,
these were not obvious and indexing was possible over a few frames.
Apparently, my beautiful crystals were in fact stacks of plates slightly
rotated with respect to each other.
Jan Abendroth wrote:
> Hi all,
> processing data collected on APS beamline BM17 on a MAR165 detector
> causes unexpected troubles. Even though the crystals are
> well-diffracting and the spots are sharp and well-resolved, indexing
> only works with a certain selection of frames, the refinement the goes
> totally hairwire. Probalby just a parameter or so set wrong. My input
> file in the attachment. The last three lines do not make much of a
> difference. Any ideas?
> Thanks!
>
> Cheers
> Jan
>
> ************************
> mosflm.in:
> detector marccd
> directory ../Images
> template Image_0###.img
> image 001
> nullpix 1
> separation 0.95 0.95 close
> !LIMITS XMIN 0 XMAX 165 YMIN 0 YMAX 165 xscan 2048 yscan 2048
> !SIZE 2048 2048
> !PIXEL 0.07934
> ************************
>
--
------------------------------------------------------------------------
Roger S. Rowlett
Professor
Colgate University Presidential Scholar
Department of Chemistry
Colgate University
13 Oak Drive
Hamilton, NY 13346
tel: (315)-228-7245
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fax: (315)-228-7935
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