Hi Elisabetta Your unit cell is pseudo F222, with twin law (-h,-k,h+k+l):
iotbx.explore_metric_symmetry --unit_cell="47.75 33.61 91.04 90.000 103.635 90.000" --space_group=C2 (output below) Did you rule out twinning? Try runing phenix.xtriage for some intensity stats and/or phenix.refine for lsq twin refinement and see where the twin fraction goes. Contact me personally if you need help or if you are not sure how to run things. HTH Peter A summary of the constructed point group graph object is given below ==================================================================== ---------------------- Input crystal symmetry ---------------------- Unit cell: (47.75, 33.609999999999999, 91.040000000000006, 90.0, 103.63500000000001, 90.0) Unit cell volume: 141990.310662 Space group: C 1 2 1 -------------------------- Lattice symmetry deduction -------------------------- Niggli cell: (29.196295141678505, 29.196295141678505, 90.088423129339745, 94.902521424695664, 97.427868096943868, 109.71853700070298) Niggli cell volume: 70995.1553311 Niggli transformed input symmetry: C 1 2 1 (x+y,-x+y+z,z) Symmetry of Niggli cell: F 2 2 2 (x-y+z,x+y+z,2*z) All pointgroups that are both a subgroup of the lattice symmetry and a supergroup of the Niggli transformed input symmetry wil now be listed, as well as their minimal supergroups/maximal subgroups and symmetry operators that generate them. For each pointgroup, a list of compatible spacegroups will be listed. Care is taken that there are no sysmetatic absence violation with the provided input spacegroup. ------------------------ Vertices and their edges ------------------------ Point group F 2 2 2 (x-y+z,x+y+z,2*z) is a maximal subgroup of : * None Point group C 1 2 1 (x+y,-x+y+z,z) is a maximal subgroup of : * F 2 2 2 (x-y+z,x+y+z,2*z) ------------------------- Transforming point groups ------------------------- >From C 1 2 1 (x+y,-x+y+z,z) to F 2 2 2 (x-y+z,x+y+z,2*z) using : * -h,-k,h+k+l ---------------------- Compatible spacegroups ---------------------- Spacegroups compatible with a specified point group **and** with the systematic absenses specified by the input space group, are listed below. Spacegroup candidates in point group F 2 2 2 (x-y+z,x+y+z,2*z): * F 2 2 2 33.61 47.75 177.01 90.00 90.00 90.00 Spacegroup candidates in point group C 1 2 1 (x+y,-x+y+z,z): * C 1 2 1 47.75 33.61 92.30 90.00 106.55 90.00 2007/8/17, Sabini, Elisabetta <[EMAIL PROTECTED]>: > Dear all, > > I have a structure at 1.6A. At the end of refinement the Rfactor and Rfree > are quite high (23/29.6%). Here are some info: > > Morphology of crystals: large but thin plates (150 x 400 x 20 microns) > Number of residues: 160 (2 x 80); 103 water molecules > Space group: C2 > Unit Cell: 47.75 33.61 91.04 90.000 103.635 90.000 > > Data is a merge of a low resolution and high resolution sweep. The > correlation between the two data sets is: > > DATA SETS NUMBER OF COMMON CORRELATION RATIO OF COMMON B-FACTOR > #i #j REFLECTIONS BETWEEN i,j INTENSITIES (i/j) BETWEEN i,j > > 1 2 4049 0.973 1.0002 0.0001 > > I include the data collection and refinement statistics in the attachment. > > Can you please suggest to me possible reasons for the high Rfact and Rfree? > > Thanks, > > Elisabetta. > > -- > Elisabetta Sabini, Ph.D. > Research Assistant Professor > University of Illinois at Chicago > Department of Biochemistry and Molecular Genetics > Molecular Biology Research Building, Rm. 1108 > 900 South Ashland Avenue > Chicago, IL 60607 > U.S.A. > > Tel: (312) 996-6299 > Fax: (312) 355-4535 > E-mail: [EMAIL PROTECTED] > >
