It probably is I2 (== C2) so it would be better to re-integrate in C2 in Mosflm, as the true beta angle may not be precisely 90deg
The CCs and R-factors are not very good, so it is worth looking at the scores for the individual 2-fold axes output by Pointless, to check that one of the axes really is much better than the other two, ie that it is I2/C2 rather than I222 If there is real doubt, it may be better to solve the structure in both space groups, and decide later which fits the data better Phil On 6 Aug 2011, at 00:15, WENHE ZHONG wrote: > Hi All, > > Recently I did some soaking experiments for crystals. Most of them did not > change their space group (I222). But one of them seems to be a little bit > different (I222 ---> I121). > The following is the pointless data: (the data was processed by Mosflm under > space group I222) > > Laue Group Lklhd NetZc Zc+ Zc- CC CC- Rmeas R- Delta > ReindexOperator > > > 1 I 1 2/m 1 ** 0.687 2.55 8.25 5.71 0.83 0.57 0.32 0.52 0.0 > > [-h,-k,l] > > 2 P -1 0.171 2.02 8.54 6.52 0.85 0.65 0.32 0.45 0.0 > > [-h,-k,1/2h+1/2k+1/2l] > - 3 I m m m 0.050 6.98 6.98 0.00 0.70 0.00 0.42 0.00 0.0 > [h,k,l] > 4 I 1 2/m 1 0.050 0.22 7.09 6.87 0.71 0.69 0.42 0.42 0.0 > [k,-h,l] > 5 I 1 2/m 1 0.043 0.06 7.05 6.99 0.70 0.70 0.42 0.42 0.0 > [h,-l,k] > > Best Solution: space group I 1 2 1 > > Reindex operator: [-h,-k,l] > Laue group probability: 0.687 > Systematic absence probability: 1.000 > Total probability: 0.687 > Space group confidence: 0.595 > Laue group confidence 0.595 > > Unit cell: 104.1 108.6 264.8 90 90 90 > > 54.32 to 3.41 - Resolution range used for Laue group search > > 54.32 to 2.25 - Resolution range in file, used for systematic absence > check > > Number of batches in file: 400 > > The data do not appear to be twinned, from the L-test > : > > WARNING: > The chosen output crystal system is different from that used for integration > of the input file(s). > You should rerun the integration in the chosen crystal system because the > cell constraints differ. > > The input crystal system is body-centred orthorhombic > (Cell: 104.1 108.6 264.8 90 90 90) > The crystal system chosen for output is body-centred monoclinic > (Cell: 104.1 108.6 264.8 90 90 90) > > I couldn't see the difference between I222 and I121. May I ask do I need to > go back to the Mosflm process step and choose other space group for the > processing? Thank you. > > King regards, > Wenhe >
