Re: [ccp4bb] space group R3(R32) or H3(H32)?
There is a lot of confusion about this! You can call it R3:H ( indexed with a=b and gamma = 120) This is also called H 3 in the PDB deposition and the CCP4 symmetry libraries. (But for the CCP4 library - it checks the axes and angles to decide whether this is using the H ( or hexagonal) convention..) The name R3:R or R3 is usually used for indexing where a=b=c, and alpha=beta=gamma. However both conventions describe the same diffraction. pointless or othercell ( from the CCP4 prereleae) will give you the reindexing transformations to change from one convention to the other. It is usually easier to visualise a protein molecule in the H3 convention but not always.. Eleanor linwoo kang wrote: Dear all Recently I collected a dataset, which is rhombohedral on indexing screen of HKL2000. I processed the dataset as R3 and R32 at synchrotron. But I realized it can be H3 or H32. Is it correct? Cell dimensions are a=b c and alpha=90, beta=90, and gamma=120. For me, synchrotron is only place to index and scale data. Can I just change space group at CCP4i from sca file processed by R3 into H3 space group or so? Because cell dimensions are same, maybe indexing can be same. Accordingly just scaling can be enough for changing space groups but I am still concerned about completeness and rejected spots, which can be different at different space groups. Please advise me! Thanks.
[ccp4bb] space group R3(R32) or H3(H32)?
Dear all Recently I collected a dataset, which is rhombohedral on indexing screen of HKL2000. I processed the dataset as R3 and R32 at synchrotron. But I realized it can be H3 or H32. Is it correct? Cell dimensions are a=b c and alpha=90, beta=90, and gamma=120. For me, synchrotron is only place to index and scale data. Can I just change space group at CCP4i from sca file processed by R3 into H3 space group or so? Because cell dimensions are same, maybe indexing can be same. Accordingly just scaling can be enough for changing space groups but I am still concerned about completeness and rejected spots, which can be different at different space groups. Please advise me! Thanks.
Re: [ccp4bb] space group R3(R32) or H3(H32)?
Dear Kang, In addition to theoretical considerations, you may want to have a look at Pointless: http://www.ccp4.ac.uk/prerelease_page.php#pointless Just integrate data with Mosflm and run Pointless before Scala (you may also want to integrate data in P1). If you want to try to import unmerged data from Denzo, you can do it using CCP4i (data reduction menu) and then try to run Pointless. Maybe it gives you useful information. Ricardo linwoo kang wrote: Dear all Recently I collected a dataset, which is rhombohedral on indexing screen of HKL2000. I processed the dataset as R3 and R32 at synchrotron. But I realized it can be H3 or H32. Is it correct? Cell dimensions are a=b c and alpha=90, beta=90, and gamma=120. For me, synchrotron is only place to index and scale data. Can I just change space group at CCP4i from sca file processed by R3 into H3 space group or so? Because cell dimensions are same, maybe indexing can be same. Accordingly just scaling can be enough for changing space groups but I am still concerned about completeness and rejected spots, which can be different at different space groups. Please advise me! Thanks.
