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Solve a small-molecule structure: Difference between revisions
→use XPREP to find possible spacegroups
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It is important that - to preserve the full information about systematic absences, for use in [[XPREP]] - XDSCONV runs in spacegroup 1. This does not necessarily mean that CORRECT also has to run in spacegroup 1, because XDS_ASCII.HKL has all observations no matter in which spacegroup the CORRECT step runs. As long as the spacegroup used in the CORRECT step is primitive, this works nicely. But if some re-indexing between CORRECT's spacegroup and P1 is necessary (like in I, F, C, R) then it is probably safest to rather just run CORRECT in P1. | It is important that - to preserve the full information about systematic absences, for use in [[XPREP]] - XDSCONV runs in spacegroup 1. This does not necessarily mean that CORRECT also has to run in spacegroup 1, because XDS_ASCII.HKL has all observations no matter in which spacegroup the CORRECT step runs. As long as the spacegroup used in the CORRECT step is primitive, this works nicely. But if some re-indexing between CORRECT's spacegroup and P1 is necessary (like in I, F, C, R) then it is probably safest to rather just run CORRECT in P1. | ||
answer the question concerning the cell axes, and then hit <Enter> several (about 6) times until the program suggests a list of spacegroups - this | Run "xprep temp.hkl", answer the question concerning the cell axes, and then hit <Enter> several (about 6) times until the program suggests a list of spacegroups - this list is going to be important. It may help to observe whether the data are centrosymmetric or not, from the line: Mean |E*E-1| = 0.939 [expected .968 centrosym and .736 non-centrosym]. Fortunately, this time there's only one spacegroup consistent with the data: | ||
<pre> | <pre> | ||
SPACE GROUP DETERMINATION | SPACE GROUP DETERMINATION | ||