Dear Eleanor Try submitting it to the STARANISO server? That does a whole slew of twinning tests (so you can take your pick from sometimes totally different twin fractions from the various tests!). Also it gives you the twin fraction rather than having you understand how to use the tests! But I agree that the L test is one of the best, and the server uses a variant of it which gives more accurate estimates of the twin fraction.
Cheers -- Ian On Tue, Oct 8, 2024 at 4:01 PM Eleanor Dodson < 0000176a9d5ebad7-dmarc-requ...@jiscmail.ac.uk> wrote: > I have always had great faith in the L test and other statistics to detect > twinning.. > But now I have a puzzling data set. > Seems to be orthorhombic with a, b and c all different > One molecule/asymm unit and no NC translation.. > BUT clear indication of twinning given by second moments, etc.. > > I have seen this before when the spacegroup was actually monoclinic and > the pointless analysis of the two fold axes along a b or c showed one was > better than the other two and in fact the crystal proved not to be twinned > when the data was processed as monoclinic.. > > But in this case no amount of reprocessing gets rid of the twin indicator > .. > Does anyone have any suggestions of why this might be? > ( The data quality isnt great - 2.5A but the Rmerges are reasonable..) > Eleanor > > > ------------------------------ > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 > ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
