Space groups F23 and P4132 are not subgroups of each other (without
invoking pseudotranslational symmetry) so they cannot be related by
twinning. The end of theoretical analysis.
Zbyszek Otwinowski
> You need to say what the cell dimensions are for these 2 options..
> Eleanor
>
> On 29 May 2012 15:59, Andrey Lebedev <[log in to unmask]> wrote:
>
>> Hi Mike.
>>
>> I would be more careful about "incorrect" space group. Yes, sometimes
>> auto-indexing gives strange results.
>> However, in your case two sets of crystals differ by two factors,
>> diffraction quality and space group.
>> Therefore it seems more likely that you have two crystal forms.
>> Could you please send me log-files from pointless or ctruncate? Then I
>> would be able to say something more definite.
>>
>> Regards
>>
>> Andrey
>>
>> On 28 May 2012, at 08:46, Mike John wrote:
>>
>> Hi, All,
>>
>> we got many datasets from crystals of our protein. when the crystal has
>> high quality, it will be indexed as F23 (correct space group). While
>> diffracting poorer, it will be indexed as incorrect space group P4132.
>> The
>> crystals are twined. My question is:
>> Given twinning, why the correct space group F23 will be indexed as an
>> incorrect space group P4132 for most of our crystals (most crystals has
>> poorer quality)? Theoretical analysis of twin operator and symmetry
>> operator to connect F23 and P4132 would be highly appreciated. Thanks
>>
>> Mike
>>
>
Zbyszek Otwinowski
UT Southwestern Medical Center at Dallas
5323 Harry Hines Blvd.
Dallas, TX 75390-8816
Tel. 214-645-6385
Fax. 214-645-6353
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