IDXREF.LP: Difference between revisions

161 bytes removed ,  9 September 2016
 
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From the difference vectors, the "reduced cell" (essentially a P1 cell, with a<b<c) has been established, together with its axes and angles. Furthermore the relation of the reciprocal cell axes (found in the beginning) with respect to the reduced cell is given. If the user supplies UNIT_CELL_CONSTANTS (and SPACE_GROUP_NUMBER >0 ) then these are converted to a reduced cell and given here.
From the difference vectors, the "reduced cell" (essentially a P1 cell, with a<b<c) has been established, together with its axes and angles. Furthermore the relation of the reciprocal cell axes (found in the beginning) with respect to the reduced cell is given. If the user supplies UNIT_CELL_CONSTANTS (and SPACE_GROUP_NUMBER >0 ) then these are converted to a reduced cell and given here.


'''If the difference vectors are not (close to) integers, something is wrong''' - see [[Problems]].


== Results from local indexing ==
== Results from local indexing ==
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               0.54                    1.00
               0.54                    1.00


This is just a little help to tell the user how big the OSCILLATION_RANGE can be without producing overlap, but it does not take the crystal's mosaicity into account, so one has to subtract the mosaicity (0.1° for good crystals, higher for normal to bad ones). Please note that the resulting value is just the '''maximum value''', ''not'' the '''optimal value'''! A '''good value''', in terms of signal-to-noise ratio, is 0.25-0.5° for CCD detectors, and around 0.1° for the Pilatus. The '''optimal value''' is the ''minimum'' of the '''maximum value''' and the '''good value'''.
This is just a little help to tell the user how big the OSCILLATION_RANGE can be without producing overlap. The maximum oscillation range is less than that given by the table, since the crystal mosaicity has to be subtracted from the table value. Please see [[Choice of OSCILLATION RANGE]].


  cpu time used                  2.8 sec
  cpu time used                  2.8 sec
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  JOB= DEFPIX INTEGRATE CORRECT
  JOB= DEFPIX INTEGRATE CORRECT
This is a feature (not a bug) to make the user aware of a possible problem.
This is a feature (not a bug) to make the user aware of a possible problem.
== See also ==
[[Indexing]]
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