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Macromolecular dictionary (mmCIF) version 2.0.09




   Residual factor R~cullis,acen~ for acentric reflections for this

   The Cullis R factor was originally defined only for centric
   reflections.  It is, however, also a useful statistical
   measure for acentric reflections, which is how it is used in
   this data item.

               sum| |Fph~obs~ +/- Fp~obs~| - Fh~calc~ |
          R~cullis,acen~ = ----------------------------------------
                       sum|Fph~obs~ - Fp~obs~|

   Fp~obs~  = the observed structure-factor amplitude of the native
   Fph~obs~ = the observed structure-factor amplitude of the
   Fh~calc~ = the calculated structure-factor amplitude from the
              heavy-atom model

   sum is taken over the specified reflections

   Ref: Cullis, A. F., Muirhead, H., Perutz, M. F., Rossmann, M. G.
        & North, A. C. T. (1961). Proc. R. Soc. London Ser. A,
        265, 15-38.

Type: float

Mandatory item: no

_phasing_MIR_der.ebi_Rcullis_acentric (ebi_extensions version 1.0)
The permitted range is [0.0, infinity)

Category: phasing_MIR_der