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Core dictionary (coreCIF) version 2.4.5




   The measure of absolute structure as defined by Flack (1983).

   For centrosymmetric structures, the only permitted value, if the
   data name is present, is 'inapplicable', represented by '.' .

   For noncentrosymmetric structures, the value must lie in the
   99.97% Gaussian confidence interval  -3u =< x =< 1 + 3u and a
   standard uncertainty (e.s.d.) u must be supplied. The
   _enumeration_range of 0.0:1.0 is correctly interpreted as
   meaning (0.0 - 3u) =< x =< (1.0 + 3u).

   Ref: Flack, H. D. (1983). Acta Cryst. A39, 876-881.

The permitted range is 0.0 -> 1.0

Type: numb

Category: refine