As far as I know all the programs we use will handle the non-primitive hexagonal setting of rhombohedral space groups (ie a=b != c, alpha=beta=90, gamma =120), often denoted "H3" or "H32" (aka R3:H in cctbx). Many of them will probably handle the primitive rhombohedral setting (a=b=c, alpha=beta=gamma), but this is much less commonly used in macromolecular crystallography, so some programs may fail to do the right thing (though they should). A space group denoted "R3" or "R32" may be in either setting, depending on the cell dimensions. I don't know what HKL2000 does, but "H32" is not primitive, it is the centred hexagonal setting.
The paper cited by Ivan presumably used the hexagonal setting, since they had c != a or b confusing I know Phil On 12 Aug 2010, at 00:42, xaravich ivan wrote: > Hello Ray, > You can contact the author of this paper. It seems they used denzo scalpack > for R32. > Ivan > > On Wed, Aug 11, 2010 at 8:53 AM, Eleanor Dodson <[email protected]> wrote: > If you cant import a file with symmetry labelled R32 but with a=b and > alpha=beta = 90, and gamma = 120 then something is wrong - the symmetry > checking looks at both name and cell.. or at least it used to.. > > The output mtz would have symmetry name changed to H32, but that is just a > name - in each case the sym ops and cell should be h32 style.. > Eleanor > > > > > Ray Brown wrote: > Hi, I have read all of the past messages about the confusion of H32 and R32 > and I want to get the correct indexing sp that I can import the .sca file > into CCP4.. > > I use DENZO and SCALEPACK in HKL2000. If you read the manual then it states > that space group R32 should only be autoindexed by DENZO on a primitive > lattice using the DENZO keyword H32. This indeed gives a primitive unit cell > and not the hexagonal setting apparently demanded by CCP4 programs. > > What do you do next? It is possible in SCALEPACK to reindex the H32 primitive > data into a rhombohedral hexagonal setting which SCALEPACK calls R32. Or > course you cannot import this .sca file into CCP4. Why not? > I can go into the .sca file and edit the header and change the R32 label to > H32. Does this screw up the indexing? > > If anybody has successfully used DENZO/SCALEPACK/CCP4 in space group R32 then > please tell me how to do it correctly. > > Cheers. > > Ray > email [email protected] > > <am0110-1.pdf>
