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Core CIF Dictionary version 2.3

_refine_ls_class_R_I_factor

Name

'_refine_ls_class_R_I_factor'

Category: refine_ls_class

Data type: numb

Must appear in a looped list containing '_refine_ls_class_code'

Enumeration range: 0.0 -> infinity

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
   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 reflections of this class.
 


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