[IUCr Home Page] [CIF Home Page]

Core CIF Dictionary version 2.3




Category: diffrn_standards

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

Enumeration range: -> 100


   The percentage decrease in the mean of the intensities
   for the set of standard reflections at the start of the
   measurement process and at the finish. This value usually
   affords a measure of the overall decay in crystal quality
   during the diffraction measurement process. Negative values
   are used in exceptional instances where the final intensities
   are greater than the initial ones.

Copyright © 2003 International Union of Crystallography

IUCr Webmaster