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Macromolecular dictionary (mmCIF) version 2.0.09

_reflns_class.R_I_factor

Name:
'_reflns_class.R_I_factor'

Definition:

   For each reflection class, the residual factor R(I) for the
   reflections judged significantly intense (i.e. satisfying the
   threshold specified by _reflns.threshold_expression) and
   included in the refinement.

   This is most often calculated in Rietveld refinements
   against 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 reflections of this class.

Type: float

Mandatory item: no

Alias:
_reflns_class_R_I_factor (cif_core.dic version 2.3)
The permitted range is [0.0, infinity)

Category: reflns_class