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Core CIF Dictionary version 2.3




Category: refine

Data type: numb

Related item: '_refine_ls_R_factor_obs'
Related function: alternate

Enumeration range: 0.0 -> infinity


   Residual factor for the reflections (with number given by
   _reflns_number_gt) judged significantly intense (i.e. satisfying
   the threshold specified by _reflns_threshold_expression)
   and included in the refinement. The reflections also satisfy
   the resolution limits established by _refine_ls_d_res_high and
   _refine_ls_d_res_low. This is the conventional R
   factor. See also _refine_ls_wR_factor_ definitions.

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

   F(obs)  = the observed structure-factor amplitudes
   F(calc) = the calculated structure-factor amplitudes

   and the sum is taken over the specified reflections

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