Sorry, I think my reply was not case in the attached images! I
happened to have the problem to see the image but I could now see all
of them. I think Tim was correct, the patterns are not the same at
all. Lijun
On Jul 16, 2010, at 12:23 PM, Lijun Liu wrote:
Dear Hui,
About the so-called "weird" pattern, it is not a surprise at all!
You mentioned you had a long-spindle shaped crystal with large cell
dimensions (208 A) and a very possible P4x2x2 SG (proved by Phil).
It is very likely the longest dimension of the crystal (parallel to
cell edge of 54.55 Å) was closely mounted parallel to the spindle
orientation during your data collection. Such an un-inclined
crystal mounting with high symmetry in this direction (4-fold),
large cell constants perpendicular to this direction, and with "big"
enough oscillation angle (could be small angle) caused this
phenomenon---weird pattern. You can check the crystal rotX and rotY
(in your P1 case also rotZ) to easily see the mounting (crystal
orientations). Also your images should also clearly tell you by
human eyes.
Though the changes of the spot positions in the "weird" pattern are
hard to tell with human eyes, the changes in intensity of the spots
should be easily seen.
Have fun!
Lijun
On Jul 16, 2010, at 8:30 AM, hui yang wrote:
Hi all,
I just collected a data set from a long-spindle-shaped crystal. The
data has been scaled to P1 space group with HKL2000, and the final
overall Rmerge is 0.208. What is strange is that, the diffraction
pattern looks all the same at different rotation angles, and the
diffraction point outside the 4A cycle are excluded automatically
and thus lead to a final resolution of 4.4A. I’m wondering 1)
Whether this crystal is twinned? 2) What is the actual space group
of it? A picture of the crystal, three images of the diffraction
pattern (1, 90 and 180), the sca file and log file have been
attached to this mail for your information.
Any suggestions and comments will be highly appreciated.
Thank you very much in advance for your inputs.
Sincerely,
Hui Yang
<data.rar>
Lijun Liu
Cardiovascular Research Institute
University of California, San Francisco
1700 4th Street, Box 2532
San Francisco, CA 94158
Phone: (415)514-2836
Lijun Liu
Cardiovascular Research Institute
University of California, San Francisco
1700 4th Street, Box 2532
San Francisco, CA 94158
Phone: (415)514-2836
