We believe that twinning can be detected from a very small subset of
the data - the moments are pretty sensitive if you dont have any specal
"features" such as pseudo translation...
Just process a few images and look at the truncate plots.
Eleanor
Chris Snook wrote:
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Soisson, Stephen Michael wrote:
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Hi everyone,
I hit the jackpot and got some beautiful crystals that are also
beautifully
twinned. If there is any good news, it is that the twin fraction is
about
0.3 for the first crystal that I collected data from. I know that some
people have collected data sets from multiple crystals until they
find one
with a lower twin fraction, and I was wondering if you can do this with
partial data sets or if you need a full set? I suppose I could test
this
out with some of my existing data; however, I thought I would pose the
question to see if anyone had direct experience with this that could
offer
any good suggestions for how to deal with this.
Many thanks in advance for your comments.
Cheers,
Steve
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Hi Stephen,
I had a similar problem a few years ago and found that I needed to
collect between 15 and 20 degrees of data for the TWIN fraction to
approach close to that of a full data set.
This was carried out on data in the P4sub3 space group so I don't know
how this would vary with a different space group. The minimum amount
of data for your space group will probably be different. You will
probably have to determine the range empirically.
I hope that helps.
Good luck
Chris
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