Crystallographic Information Framework

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Index

Macromolecular dictionary (mmCIF) version 2.0.09

_reflns.threshold_expression

Name:
'_reflns.threshold_expression'

Definition:

   The threshold, usually based on multiples of u(I), u(F^2^)
   or u(F), that serves to identify significantly intense
   reflections, the number of which is given by _reflns.number_gt.
   These reflections are used in the calculation of
   _refine.ls_R_factor_gt.

Example:

I>2u(I)

Type: text

Mandatory item: no

Alias:
_reflns_threshold_expression (cif_core.dic version 2.3)

Related item: _reflns.observed_criterion (alternate)

Category: reflns


International Tables for Crystallography

Volume G: Definition and exchange of crystallographic data

First online edition (2006)

Edited by S. R. Hall and B. McMahon

An essential guide and reference to CIF for programmers, data managers handling crystal-structure information and practising crystallographers.