Macromolecular dictionary (mmCIF) version 2.0.09
_phasing_MIR_der.R_cullis_acentric
Name:'_phasing_MIR_der.R_cullis_acentric'
Definition:
Residual factor R~cullis,acen~ for acentric reflections for this
derivative.
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
derivative
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
Alias:_phasing_MIR_der.ebi_Rcullis_acentric (ebi_extensions version 1.0)
The permitted range is [0.0, infinity)
Category: phasing_MIR_der


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