Re: [ccp4bb] Triclinic solution for a dataset with pseudo-translational symmetry, possible pseudo-centering and possible pseudo-merohedral twinning. How to proceed?

On Mon, 21 Oct 2013 23:28:48 -0500, Stefan Gajewski sgajew...@gmail.com wrote: ... 5) tetartohedral twinning? what refinement software is able to deal with that? Refmac HTH, Kay

[ccp4bb] AW: [ccp4bb] Triclinic solution for a dataset with pseudo-translational symmetry, possible pseudo-centering and possible pseudo-merohedral twinning. How to proceed?

Dear Stefan, Congratulations! It seems that you not only have pseudo-translation and pseudo 4-fold symmetry in your diffraction, but also pseudo 8-fold symmetry in your protein molecules! An excellent case to learn a lot about space groups and NCS symmetry. 3) you are right, you might see

[ccp4bb] Triclinic solution for a dataset with pseudo-translational symmetry, possible pseudo-centering and possible pseudo-merohedral twinning. How to proceed?

Dear experts, This is a messy question concerning a messy dataset and I try to put it correctly. I have a severely anisotropic dataset up to 2.3A that merges quite fine in all 4/mmm. Automatic indexing is primitive tetragonal but I can push it to a centered tetragonal cell if I want to. The

[ccp4bb] AW: [ccp4bb] Triclinic solution for a dataset with pseudo-translational symmetry, possible pseudo-centering and possible pseudo-merohedral twinning. How to proceed?

Dear Stefan, The picture you give of your crystals is indeed quite messy. The first thing I would do is to sort all the information at hand and try to see what could be going on. Based on the (limited) information you give, I have to following comments: 1) Autoindexing suggests a