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Core CIF Dictionary version 2.3




Category: refine

Data type: numb

Enumeration range: 0.0 -> infinity


   Residual factor R(I) for significantly intense reflections
   (satisfying _reflns_threshold_expression) and included in
   the refinement.

   This is most often calculated in Rietveld refinements of powder
   data, where it is referred to as R~B~ or R~Bragg~.

           sum | I(obs) - I(calc) |
   R(I) =  ------------------------
                  sum | I(obs) |

   I(obs)  = the net observed intensities
   I(calc) = the net calculated intensities

   and the sum is taken over the specified reflections

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