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Core CIF Dictionary version 2.3

_refine_ls_abs_structure_Flack

Name

'_refine_ls_abs_structure_Flack'

Category: refine

Data type: numb (with optional s.u. in parentheses)

Enumeration range: 0.0 -> 1.0

Definition

    	
   The measure of absolute structure as defined by Flack.

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

   For non-centrosymmetric structures the value must lie in the
   99.97% Gaussian confidence interval  -3u =Permitted values:
_range of 0.0:1.0 is correctly interpreted as meaning (0.0 - 3u) =
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